H. Brüggenwirth - Academia.edu (original) (raw)

Papers by H. Brüggenwirth

Research paper thumbnail of Hormonal evaluation in relation to phenotype and genotype in 286 patients with a disorder of sex development from Indonesia

Clinical Endocrinology, 2016

This is the author manuscript accepted for publication and has undergone full peer review but has... more This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as

Research paper thumbnail of Influence of sex of the transmitting parent as well as of parental allele size on the CTG expansion in myotonic dystrophy (DM)

American journal of human genetics, 1993

In patients with myotonic dystrophy (DM), the severity of clinical signs is correlated with the l... more In patients with myotonic dystrophy (DM), the severity of clinical signs is correlated with the length of a (CTG)n trinucleotide repeat sequence. This sequence tends to expand in subsequent generations. In order to examine the kinetics of this process and, in particular, the influence of the mutant-allele size and the sex of the transmitting parent, we have studied (CTG)n repeat lengths in the offspring of 38 healthy carriers with small mutations (less than 100 CTG trinucleotides, mean length [CTG]67). In these studies, we found a weakly positive correlation between the size of the mutation in the carrier parents and that in their offspring. Furthermore, we observed that, in the offspring of male transmitters, repeat lengths exceeding 100 CTG trinucleotides were much more frequent than in the offspring of carrier females (48 [92%] of 52 vs. 7 [44%] of 16, P = .0002). Similarly, in genealogical studies performed in 38 Dutch DM kindreds, an excess of nonmanifesting male transmitters w...

Research paper thumbnail of Variable Loss of Functional Activities of Androgen Receptor Mutants in Patients with Androgen Insensitivity Syndrome

Sexual Development, 2013

Androgen receptor (AR) mutations in androgen insensitivity syndrome (AIS) are associated with a v... more Androgen receptor (AR) mutations in androgen insensitivity syndrome (AIS) are associated with a variety of clinical phenotypes. The aim of the present study was to compare the molecular properties and potential pathogenic nature of 8 novel and 3 recurrent AR variants with a broad variety of functional assays. Eleven AR variants (p.Cys177Gly, p.Arg609Met, p.Asp691del, p.Leu701Phe, p.Leu723Phe, p.Ser741Tyr, p.Ala766Ser, p.Arg775Leu, p.Phe814Cys, p.Lys913X, p.Ile915Thr) were analyzed for hormone binding, transcriptional activation, cofactor binding, translocation to the nucleus, nuclear dynamics, and structural conformation. Ligand-binding domain variants with low to intermediate transcriptional activation displayed aberrant Kd values for hormone binding and decreased nuclear translocation. Transcriptional activation data, FxxFF-like peptide binding and DNA binding correlated well for all variants, except for p.Arg609Met, p.Leu723Phe and p.Arg775Leu, which displayed a relatively higher...

Research paper thumbnail of Complete androgen insensitivity syndrome: factors influencing gonadal histology including germ cell pathology

Research paper thumbnail of GenotypeVersusPhenotype in Families with Androgen Insensitivity Syndrome

The Journal of Clinical Endocrinology & Metabolism, 2001

Androgen insensitivity syndrome encompasses a wide range of phenotypes, which are caused by numer... more Androgen insensitivity syndrome encompasses a wide range of phenotypes, which are caused by numerous different mutations in the AR gene. Detailed information on the genotype/ phenotype relationship in androgen insensitivity syndrome is important for sex assignment, treatment of androgen insensitivity syndrome patients, genetic counseling of their families, and insight into the functional domains of the AR. The commonly accepted concept of dependence on fetal androgens of the development of Wolffian ducts was studied in complete androgen insensitivity syndrome (CAIS) patients. In a nationwide survey in The Netherlands, all cases (n ‫؍‬ 49) with the presumptive diagnosis androgen insensitivity syndrome known to pediatric endocrinologists and clinical geneticists were studied. After studying the clinical phenotype, mutation analysis and functional analysis of mutant receptors were performed using genital skin fibroblasts and in vitro expression studies. Here we report the findings in families with multiple affected cases. Fifty-nine percent of androgen insensitivity syndrome patients had other affected relatives. A total of 17 families were studied, seven families with CAIS (18 patients), nine families with partial androgen insensitivity (24 patients), and one family with female prepubertal phenotypes (two patients). No phenotypic variation was observed in families with CAIS. However, phenotypic variation was observed in one-third of families with partial androgen insensitivity resulting in different sex of rearing and differences in requirement of reconstructive surgery. Intrafamilial phenotypic variation was observed for mutations R846H, M771I, and deletion of amino acid N682. Four newly identified mutations

Research paper thumbnail of Pubertal androgenization and gonadal histology in two 46,XY adolescents with NR5A1 mutations and predominantly female phenotype at birth

European Journal of Endocrinology, 2012

ObjectiveMost patients with NR5A1 (SF-1) mutations and poor virilization at birth are sex-assigne... more ObjectiveMost patients with NR5A1 (SF-1) mutations and poor virilization at birth are sex-assigned female and receive early gonadectomy. Although studies in pituitary-specific Sf-1 knockout mice suggest hypogonadotropic hypogonadism, little is known about endocrine function at puberty and on germ cell tumor risk in patients with SF-1 mutations. This study reports on the natural course during puberty and on gonadal histology in two adolescents with SF-1 mutations and predominantly female phenotype at birth.Design and methodsClinical and hormonal data and histopathological studies are reported in one male and one female adolescent with, respectively, a nonsense mutation (c.9T>A, p.Tyr3X) and a deletion of the first two coding exons (NCBI36/hg18 Chr9:g.(126306276-126307705)_(126303229-126302828)del) of NR5A1, both predicted to fully disrupt gene function.ResultsLH and testosterone concentrations were in the normal male range, virilization was disproportionate to the neonatal phenoty...

Research paper thumbnail of Substitution of Ala564 in the First Zinc Cluster of the Deoxyribonucleic Acid (DNA)-Binding Domain of the Androgen Receptor by Asp, Asn, or Leu Exerts Differential Effects on DNA Binding*

Endocrinology, 1998

In the androgen receptor of a patient with androgen insensitivity, the alanine residue at positio... more In the androgen receptor of a patient with androgen insensitivity, the alanine residue at position 564 in the first zinc cluster of the DNA-binding domain was substituted by aspartic acid. In other members of the steroid receptor family, either valine or alanine is present at the corresponding position, suggesting the importance of a neutral amino acid residue at this site. The mutant receptor was transcriptionally inactive, which corresponded to the absence of specific DNA binding in gel retardation assays, and its inactivity in a promoter interference assay. Two other receptor mutants with a mutation at this same position were created to study the role of position 564 in the human androgen receptor on DNA binding in more detail. Introduction of asparagine at position 564 resulted in transcription activation of a mouse mammary tumor virus promoter, although at a lower level compared with the wild-type receptor. Transcription activation of an (ARE)2-TATA promoter was low, and bindin...

Research paper thumbnail of Familial gigantism caused by anNSD1 mutation

American Journal of Medical Genetics Part A, 2005

A three-generation family with autosomal dominant segregation of a novel NSD1 mutation (6605G --&... more A three-generation family with autosomal dominant segregation of a novel NSD1 mutation (6605G --> A, resulting in Cys2202Tyr) is reported. Haploinsufficiency of NSD1 has been identified as the major cause of Sotos syndrome. The overgrowth condition (MIM 117550) is characterized by facial anomalies, macrocephaly, advanced bone age, and learning disabilities. Manifestations in the present family include dramatically increased height, weight, and head circumference together with a long face, large mandible, and large ears, but mental deficiency was absent.

Research paper thumbnail of Residual N-acetyl-α-glucosaminidase activity in fibroblasts correlates with disease severity in patients with mucopolysaccharidosis type IIIB

Journal of inherited metabolic disease, 2016

Mucopolysaccharidosis type IIIB (MPS IIIB) is a rare genetic disorder in which the deficiency of ... more Mucopolysaccharidosis type IIIB (MPS IIIB) is a rare genetic disorder in which the deficiency of the lysosomal enzyme N-acetyl-α-glucosaminidase (NAGLU) results in the accumulation of heparan sulfate (HS), leading to progressive neurocognitive deterioration. In MPS IIIB a wide spectrum of disease severity is seen. Due to a large allelic heterogeneity, establishing genotype-phenotype correlations is difficult. However, reliable prediction of the natural course of the disease is needed, in particular for the assessment of the efficacy of potential therapies. To identify markers that correlate with disease severity, all Dutch patients diagnosed with MPS IIIB were characterised as either rapid (RP; classical, severe phenotype) or slow progressors (SP; non-classical, less severe phenotype), based on clinical data. NAGLU activity and HS levels were measured in patients' fibroblasts after culturing at different temperatures. A small, though significant difference in NAGLU activity was ...

Research paper thumbnail of Post-zygotic mutations and somatic mosaicism in androgen insensitivity syndrome

Trends in Genetics, 2001

Holterhus et al. (this issue) correctly point out that we did indeed misinterpret part of their r... more Holterhus et al. (this issue) correctly point out that we did indeed misinterpret part of their results concerning the possibility that some cases of androgen insensitivity syndrome (AIS) could be due to somatic mosaicism caused by the back mutation of mutant androgen receptors to wild-type in some androgen responsive tissues. However, although back mutations have not yet been proven to be a source of somatic mosaicism in cases of AIS, there are a number of other cases in the literature where back mutations do indeed result in somatic mosaicism1xReverse mutations – spontaneous amelioration or cure of inherited disorders?. Wahn, V. et al. Eur. J. Pediatr. 1998; 157: 613–617Crossref | PubMed | Scopus (6)See all References, 2xRevertant mosaicism in human genetic disorders. Jonkman, M.F. Am. J. Med. Genet. 1999; 85: 361–364Crossref | PubMed | Scopus (34)See all References, 3xBack mutations can produce phenotype reversion in Bloom syndrome somatic cells. Ellis, N.A. et al. Hum. Genet. 2001; 108: 167–173Crossref | PubMed | Scopus (20)See all References.We are also grateful that they chose to reinforce the importance of such information for genetic counseling, particularly because the occurrence of somatic mosaicism has recently been shown to be more than just an isolated series of events in a number of genetic disorders. In these conditions, which include hemophilia A (Ref. 4xSomatic mosaicism in Hemophilia A: a fairly common event. Leuer, M. et al. Am. J. Hum. Genet. 2001; 69: 75–87Abstract | Full Text | Full Text PDF | PubMed | Scopus (83)See all ReferencesRef. 4), hemophilia B (Ref. 5xGermline origins in the human F9 gene: frequent G:C(A:T mosaicism and increased mutations with advanced maternal age. Ketterling, R.P. et al. Hum. Genet. 1999; 105: 629–640Crossref | PubMed | Scopus (30)See all ReferencesRef. 5), retinoblastoma6xFrequency of somatic and germ-line mosaicism in Retinoblastoma: implications for genetic counseling. Sippel, K.C. et al. Am. J. Hum. Genet. 1998; 62: 610–619Abstract | Full Text | Full Text PDF | PubMed | Scopus (106)See all References6 and tuberous sclerosis complex7xHigh rate of mosaicism in tuberous sclerosis complex. Verhoef, S. et al. Am. J. Hum. Genet. 1999; 64: 1632–1637Abstract | Full Text | Full Text PDF | PubMed | Scopus (99)See all References7, somatic mosaicism can occur at a frequency of 10–20%. Furthermore, these studies also note that somatic mosaicism is a possible source not only of variable expressivity, but also of altered penetrance.These observations add weight to our hypothesis that, with the recently acquired ability to sequence specific tissues easily and efficiently, somatic mosaicism is increasingly likely to be observed as a source of variable expressivity in many disorders and diseases.

Research paper thumbnail of HLA frequencies and associations in cystic fibrosis

Tissue Antigens, 2013

Cystic fibrosis (CF) is classically attributed to the dysfunction of the single CF transmembrane ... more Cystic fibrosis (CF) is classically attributed to the dysfunction of the single CF transmembrane conductance regulator gene. The incidence of human leukocyte antigen (HLA) polymorphisms in different CF-associated diseases raises the question of an unequal distribution of HLA genotypes in CF. This study aimed to evaluate HLA gene frequencies and possible associations in CF patients compared with a control population. Frequencies of HLA-DRB1, HLA-DQA1 and HLA-DQB1, performed by intermediate resolution typing using Luminex sequence-specific oligonucleotide, and epitope counts were similar in 340 CF patients when compared with 400 control subjects. In conclusion, HLA-DRB1,-DQA1 and-DQB1 do not seem to influence susceptibility to CF. Whether HLA plays a role in the severity of CF disease needs to be investigated.

Research paper thumbnail of Differential diagnosis in spinal and bulbar muscular atrophy clinical and molecular aspects

Journal of the Neurological Sciences, 1995

Kennedy disease is caused by an enlarged trinucleotide repeat sequence within the androgen recept... more Kennedy disease is caused by an enlarged trinucleotide repeat sequence within the androgen receptor gene. We report here seven male patients with a benign motor neuron syndrome highly analogous to Kennedy disease but with a normal trinucleotide repeat.

Research paper thumbnail of Advanced Pubertal Development in Two Adolescents with New SF-1 Mutations

Journal of Pediatric Urology, 2010

The cosmetic results of reconstructive surgery for girls with congenital adrenal hyperplasia have... more The cosmetic results of reconstructive surgery for girls with congenital adrenal hyperplasia have improved significantly over the past two decades. However, one component that is less than perfect is the appearance of the clitoris, particularly its dorsal skin cover. This presentation describes an approach to managing the dorsal skin cover that consistently results in a naturally hooded clitoris and reduces the need for excisional reduction of the size of the glans clitoris except in the severely hypertrophied cases. MATERIAL AND METHODS Rather than separate the dorsal mucosal attachments to the glans clitoris, they are left intact and the circumferential skin incision is shifted proximally, at the point which would form the base of the reduced clitoral shaft. The shaft skin proximal to that is split in the midline and used for construction of the labia minora. And the circumscribing incision is sutured to the apex of the midline dorsal incision. RESULTS This procedure has been used successfully in 3 patients with excellent intermediate results (6-12 months).The clitoris retained a natural position and hooded appearance. There was no cross healing or other complications.

Research paper thumbnail of Mosaicism due to a Somatic Mutation of the Androgen Receptor Gene Determines Phenotype in Androgen Insensitivity Syndrome1

The Journal of Clinical Endocrinology & Metabolism, 1997

Premature stop codons of the human androgen receptor (AR) gene are usually associated with a comp... more Premature stop codons of the human androgen receptor (AR) gene are usually associated with a complete androgen insensitivity syndrome. We, however, identified an adult patient with a 46,XY karyotype carrying a premature stop codon in exon 1 of the AR gene presenting with signs of partial virilization: pubic hair Tanner stage 4 and clitoral enlargement. No other family members were affected. A point mutation at codon position 172 of the AR gene was detected that replaced the original TTA (Leu) with a premature stop codon TGA (opal). Careful examination of the sequencing gel, however, also identified a wild-type allele, indicating a mosaicism. In addition, elimination of the unique AflII recognition site induced by the mutation was incomplete, thus confirming the coexistence of mutant and wild-type AR alleles in the patient. Normal R1881 binding and a normal 110/112-kDa AR doublet in Western immunoblots consolidated the molecular genetic data by demonstrating the expression of the wil...

Research paper thumbnail of Gene Expression Profiling in Uveal Melanoma: Two Regions on 3p Related to Prognosis

Investigative Opthalmology & Visual Science, 2008

PURPOSE. Although studies on uveal melanoma (UM) revealed prognostic significance of chromosomal ... more PURPOSE. Although studies on uveal melanoma (UM) revealed prognostic significance of chromosomal aberrations, they resulted in classification errors in survival prediction. A robust prognostic classifier with strong predictive value and further insight in genes responsible for poor prognosis were obtained by performing a gene-expression profile in tumors of UM patients for which extensive clinical, histopathologic, cytogenetic, and follow-up data were available. Furthermore, the UM microarray expression data were compared with cytogenetic data. METHODS. Gene-expression profiles of 46 UMs were obtained with microchip assays. Data were analyzed with cluster-analysis and predictive analysis of microarrays (PAM) software and validated with real-time PCR. The prognostic significance of UMs with specific molecular signatures was determined. Furthermore, LAP analysis resulted in the identification of differentially expressed chromosomal regions. RESULTS. The primary UMs were classified in two distinct molecular classes with a strong prognostic value (P Ͻ 0.001; hazard ratio 7.7). Classifier gene sets for microarray class and disease-free survival were validated with real-time PCR, and the predictive value of the UM class marker set was validated with gene-expression profiles of tumors provided by other institutions, showing a sensitivity of 0.93 and specificity of 1.00 for class II tumors. A locally adaptive statistical procedure identified two regions on the short arm of chromosome 3 with decreased gene-expression in tumors with shorter disease-free survival. CONCLUSIONS. Microarray classification outperforms known prognostic indicators for UM, such as clinical, histopathologic, and cytogenetic parameters. In addition, the identified regions with lower expressed genes on 3p could harbor genes that are responsible for the poor prognosis of patients with UM.

Research paper thumbnail of A DGGE system for comprehensive mutation screening ofBRCA1andBRCA2: application in a Dutch cancer clinic setting

Human Mutation, 2006

Communicated by Dvorah Abeliovich Rapid and reliable identification of deleterious changes in the... more Communicated by Dvorah Abeliovich Rapid and reliable identification of deleterious changes in the breast cancer genes BRCA1 and BRCA2 has become one of the major issues in most DNA services laboratories. To rapidly detect all possible changes within the coding and splice site determining sequences of the breast cancer genes, we established a semiautomated denaturing gradient gel electrophoresis (DGGE) mutation scanning system. All exons of both genes are covered by the DGGE scan, comprising 120 amplicons. We use a semiautomated approach, amplifying all individual amplicons with the same PCR program, after which the amplicons are pooled. DGGE is performed using three slightly different gel conditions. Validation was performed using DNA samples with known sequence variants in 107 of the 120 amplicons; all variants were detected. This DGGE mutation scanning, in combination with a PCR test for two Dutch founder deletions in BRCA1 was then applied in 431 families in which 52 deleterious changes and 70 unclassified variants were found. Fifteen unclassified variants were not reported before. The system was easily adopted by five other laboratories, where in another 3,593 families both exons 11 were analyzed by the protein truncation test (PTT) and the remaining exons by DGGE. In total, a deleterious change (nonsense, frameshift, splice-site mutation, or large deletion) was found in 661 families (16.4%), 462 in BRCA1 (11.5%), 197 in BRCA2 (4.9%), and in two index cases a deleterious change in both BRCA1 and BRCA2 was identified. Eleven deleterious changes in BRCA1 and 36 in BRCA2 had not been reported before. In conclusion, this DGGE mutation screening method for BRCA1 and BRCA2 is proven to be highly sensitive and is easy to adopt, which makes screening of large numbers of patients feasible. The results of screening of BRCA1 and BRCA2 in more than 4,000 families present a valuable overview of mutations in the Dutch population.

Research paper thumbnail of Survival and prognostic factors in BRCA1-associated breast cancer

Annals of Oncology, 2006

Studies comparing survival in BRCA1-associated and sporadic breast cancer (BC) report inconsisten... more Studies comparing survival in BRCA1-associated and sporadic breast cancer (BC) report inconsistent results and frequently concern small sample sizes. Further, the prognostic impact of the classical tumour and treatment factors is unclear in BRCA1-associated BC. We selected 223 BC patients diagnosed between 1980 and 2001 within families with a deleterious germline BRCA1-mutation ascertained at the Rotterdam Family Cancer Clinic. To correct for ascertainment bias, the group of index patients undergoing DNA testing more than 2 years after BC diagnosis (n = 53) was separated from the other BRCA1-patients (n = 170). All BRCA1-associated patients were matched in a 1:2 ratio for age and year of diagnosis to sporadic BC patients. We compared the occurrence of ipsi- and contralateral BC (CBC) as well as distant disease-free (DDFS), BC-specific (BCSS) and overall survival (OS). By multivariate modelling, the prognostic impact of tumour and treatment factors was investigated separately in BRCA1-associated and sporadic breast cancers. For the total group of 669 cases, the median follow-up was 5.1 years, the median age at diagnosis 39 years. We confirmed the existence of the typical BRCA1-associated tumour type and the high CBC incidence. No significant differences between BRCA1-associated and sporadic tumours were found with respect to ipsilateral BC recurrence (HR(mult) 0.7; P = 0.24), DDFS (HR(mult) 1.2; P = 0.37) or BC-specific survival (HR(mult) 1.3; P = 0.23). A trend towards a worse survival was found for BRCA1-associated ductal BC (HR(mult) 1.5, P = 0.07). Prognostic factors for BRCA1-associated BC were age at diagnosis, tumour size and morphology, and nodal status. Further, survival was non-significantly improved by systemic treatment and a bilateral salpingo-oophorectomy. No effect on survival of a contralateral prophylactic mastectomy was seen. BRCA1-associated BC is characterised by specific tumour characteristics, a high incidence of CBC and a trend towards a worse survival for the ductal tumour type. Our observation that tumour size and nodal status are also prognostic factors for BRCA1-associated BC implies that the strategy to use these factors as a proxy for ultimate mortality, for instance in BC screening programmes or the consideration of (contralateral) preventive mastectomy, appears to be valid in this specific group of patients.

Research paper thumbnail of Anticipation resulting in elimination of the myotonic dystrophy gene: a follow up study of one extended family

Journal of Medical Genetics, 1994

Research paper thumbnail of Molecular Analysis of the Androgen-Receptor Gene in a Family with Receptor-Positive Partial Androgen Insensitivity: An Unusual Type of Intronic Mutation

The American Journal of Human Genetics, 1997

In the coding part and the intron-exon boundaries of the androgen-receptor gene of a patient with... more In the coding part and the intron-exon boundaries of the androgen-receptor gene of a patient with partial androgen insensitivity, no mutation was found. The androgen receptor of this patient displayed normal ligand-binding parameters and migrated as a 110-112-kD doublet on SDS-PAGE in the absence of hormone. However, after culturing of the patient's genital skin fibroblasts in the presence of hormone, the slowermigrating 114-kD protein, which reflects hormonedependent phosphorylation, was hardly detectable. Furthermore, receptor protein was undetectable in the nuclear fraction of the fibroblasts, after treatment with hormone, which is indicative of defective DNA binding. By sequencing part of intron 2, a TrA mutation was found 11 bp upstream of exon 3. In our screening of 102 chromosomes from unrelated individuals, this basepair substitution was not found, indicating that it was not a polymorphism. mRNA analysis revealed that splicing involved a cryptic splice site, located 71/70 bp upstream of exon 3, resulting in generation of mRNA with an insert of 69 nucleotides. In addition, a small amount of a transcript with a deleted exon 3 and a very low level of wild-type transcript were detected. Translation of the extended transcript resulted in an androgen-receptor protein with 23 amino acid residues inserted between the two zinc clusters, displaying defective DNA binding and defective transcription activation.

Research paper thumbnail of A NovelAMHMissense Mutation in a Patient with Persistent Müllerian Duct Syndrome

Sexual Development, 2012

external genitalia under influence of hormones produced by the gonads [Wilhelm et al., 2007; Fran... more external genitalia under influence of hormones produced by the gonads [Wilhelm et al., 2007; Franco and Yao, 2012]. Testosterone produced by testicular Leydig cells will induce the differentiation of the male reproductive tract, i.e. the Wolffian ducts, into epididymis, vas deferens, and seminal vesicles. Anti-Müllerian hormone (AMH), produced by the testicular Sertoli cells, is responsible for the regression of the Müllerian ducts. In the absence of AMH the Müllerian ducts will develop into normal female internal organs [Behringer et al., 1994]. Persistent Müllerian duct syndrome (PMDS) is characterized by the presence of a uterus, fallopian tubes and the upper part of the vagina in phenotypic normal male patients, and is usually discovered at surgery for cryptorchidism or inguinal hernias. AMH, a member of the transforming growth factor ␤ (TGF ␤) family, signals through a heterodimeric receptor complex consisting of a specific type II receptor (AMHRII) and shared type I receptors (ALK2, 3, and 6) [Visser, 2003; Orvis et al., 2008]. In approximately 85% of the cases mutations within the AMH and AMHR2 genes are responsible for this error in sex differentiation [Josso et al., 2005]. Mutations in the 3 type I receptor genes have not been detected [Josso et al., 2005], and thus for the remaining 15% of the cases the causative genes remain to be identified. Patients with mutations in

Research paper thumbnail of Hormonal evaluation in relation to phenotype and genotype in 286 patients with a disorder of sex development from Indonesia

Clinical Endocrinology, 2016

This is the author manuscript accepted for publication and has undergone full peer review but has... more This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as

Research paper thumbnail of Influence of sex of the transmitting parent as well as of parental allele size on the CTG expansion in myotonic dystrophy (DM)

American journal of human genetics, 1993

In patients with myotonic dystrophy (DM), the severity of clinical signs is correlated with the l... more In patients with myotonic dystrophy (DM), the severity of clinical signs is correlated with the length of a (CTG)n trinucleotide repeat sequence. This sequence tends to expand in subsequent generations. In order to examine the kinetics of this process and, in particular, the influence of the mutant-allele size and the sex of the transmitting parent, we have studied (CTG)n repeat lengths in the offspring of 38 healthy carriers with small mutations (less than 100 CTG trinucleotides, mean length [CTG]67). In these studies, we found a weakly positive correlation between the size of the mutation in the carrier parents and that in their offspring. Furthermore, we observed that, in the offspring of male transmitters, repeat lengths exceeding 100 CTG trinucleotides were much more frequent than in the offspring of carrier females (48 [92%] of 52 vs. 7 [44%] of 16, P = .0002). Similarly, in genealogical studies performed in 38 Dutch DM kindreds, an excess of nonmanifesting male transmitters w...

Research paper thumbnail of Variable Loss of Functional Activities of Androgen Receptor Mutants in Patients with Androgen Insensitivity Syndrome

Sexual Development, 2013

Androgen receptor (AR) mutations in androgen insensitivity syndrome (AIS) are associated with a v... more Androgen receptor (AR) mutations in androgen insensitivity syndrome (AIS) are associated with a variety of clinical phenotypes. The aim of the present study was to compare the molecular properties and potential pathogenic nature of 8 novel and 3 recurrent AR variants with a broad variety of functional assays. Eleven AR variants (p.Cys177Gly, p.Arg609Met, p.Asp691del, p.Leu701Phe, p.Leu723Phe, p.Ser741Tyr, p.Ala766Ser, p.Arg775Leu, p.Phe814Cys, p.Lys913X, p.Ile915Thr) were analyzed for hormone binding, transcriptional activation, cofactor binding, translocation to the nucleus, nuclear dynamics, and structural conformation. Ligand-binding domain variants with low to intermediate transcriptional activation displayed aberrant Kd values for hormone binding and decreased nuclear translocation. Transcriptional activation data, FxxFF-like peptide binding and DNA binding correlated well for all variants, except for p.Arg609Met, p.Leu723Phe and p.Arg775Leu, which displayed a relatively higher...

Research paper thumbnail of Complete androgen insensitivity syndrome: factors influencing gonadal histology including germ cell pathology

Research paper thumbnail of GenotypeVersusPhenotype in Families with Androgen Insensitivity Syndrome

The Journal of Clinical Endocrinology & Metabolism, 2001

Androgen insensitivity syndrome encompasses a wide range of phenotypes, which are caused by numer... more Androgen insensitivity syndrome encompasses a wide range of phenotypes, which are caused by numerous different mutations in the AR gene. Detailed information on the genotype/ phenotype relationship in androgen insensitivity syndrome is important for sex assignment, treatment of androgen insensitivity syndrome patients, genetic counseling of their families, and insight into the functional domains of the AR. The commonly accepted concept of dependence on fetal androgens of the development of Wolffian ducts was studied in complete androgen insensitivity syndrome (CAIS) patients. In a nationwide survey in The Netherlands, all cases (n ‫؍‬ 49) with the presumptive diagnosis androgen insensitivity syndrome known to pediatric endocrinologists and clinical geneticists were studied. After studying the clinical phenotype, mutation analysis and functional analysis of mutant receptors were performed using genital skin fibroblasts and in vitro expression studies. Here we report the findings in families with multiple affected cases. Fifty-nine percent of androgen insensitivity syndrome patients had other affected relatives. A total of 17 families were studied, seven families with CAIS (18 patients), nine families with partial androgen insensitivity (24 patients), and one family with female prepubertal phenotypes (two patients). No phenotypic variation was observed in families with CAIS. However, phenotypic variation was observed in one-third of families with partial androgen insensitivity resulting in different sex of rearing and differences in requirement of reconstructive surgery. Intrafamilial phenotypic variation was observed for mutations R846H, M771I, and deletion of amino acid N682. Four newly identified mutations

Research paper thumbnail of Pubertal androgenization and gonadal histology in two 46,XY adolescents with NR5A1 mutations and predominantly female phenotype at birth

European Journal of Endocrinology, 2012

ObjectiveMost patients with NR5A1 (SF-1) mutations and poor virilization at birth are sex-assigne... more ObjectiveMost patients with NR5A1 (SF-1) mutations and poor virilization at birth are sex-assigned female and receive early gonadectomy. Although studies in pituitary-specific Sf-1 knockout mice suggest hypogonadotropic hypogonadism, little is known about endocrine function at puberty and on germ cell tumor risk in patients with SF-1 mutations. This study reports on the natural course during puberty and on gonadal histology in two adolescents with SF-1 mutations and predominantly female phenotype at birth.Design and methodsClinical and hormonal data and histopathological studies are reported in one male and one female adolescent with, respectively, a nonsense mutation (c.9T>A, p.Tyr3X) and a deletion of the first two coding exons (NCBI36/hg18 Chr9:g.(126306276-126307705)_(126303229-126302828)del) of NR5A1, both predicted to fully disrupt gene function.ResultsLH and testosterone concentrations were in the normal male range, virilization was disproportionate to the neonatal phenoty...

Research paper thumbnail of Substitution of Ala564 in the First Zinc Cluster of the Deoxyribonucleic Acid (DNA)-Binding Domain of the Androgen Receptor by Asp, Asn, or Leu Exerts Differential Effects on DNA Binding*

Endocrinology, 1998

In the androgen receptor of a patient with androgen insensitivity, the alanine residue at positio... more In the androgen receptor of a patient with androgen insensitivity, the alanine residue at position 564 in the first zinc cluster of the DNA-binding domain was substituted by aspartic acid. In other members of the steroid receptor family, either valine or alanine is present at the corresponding position, suggesting the importance of a neutral amino acid residue at this site. The mutant receptor was transcriptionally inactive, which corresponded to the absence of specific DNA binding in gel retardation assays, and its inactivity in a promoter interference assay. Two other receptor mutants with a mutation at this same position were created to study the role of position 564 in the human androgen receptor on DNA binding in more detail. Introduction of asparagine at position 564 resulted in transcription activation of a mouse mammary tumor virus promoter, although at a lower level compared with the wild-type receptor. Transcription activation of an (ARE)2-TATA promoter was low, and bindin...

Research paper thumbnail of Familial gigantism caused by anNSD1 mutation

American Journal of Medical Genetics Part A, 2005

A three-generation family with autosomal dominant segregation of a novel NSD1 mutation (6605G --&... more A three-generation family with autosomal dominant segregation of a novel NSD1 mutation (6605G --> A, resulting in Cys2202Tyr) is reported. Haploinsufficiency of NSD1 has been identified as the major cause of Sotos syndrome. The overgrowth condition (MIM 117550) is characterized by facial anomalies, macrocephaly, advanced bone age, and learning disabilities. Manifestations in the present family include dramatically increased height, weight, and head circumference together with a long face, large mandible, and large ears, but mental deficiency was absent.

Research paper thumbnail of Residual N-acetyl-α-glucosaminidase activity in fibroblasts correlates with disease severity in patients with mucopolysaccharidosis type IIIB

Journal of inherited metabolic disease, 2016

Mucopolysaccharidosis type IIIB (MPS IIIB) is a rare genetic disorder in which the deficiency of ... more Mucopolysaccharidosis type IIIB (MPS IIIB) is a rare genetic disorder in which the deficiency of the lysosomal enzyme N-acetyl-α-glucosaminidase (NAGLU) results in the accumulation of heparan sulfate (HS), leading to progressive neurocognitive deterioration. In MPS IIIB a wide spectrum of disease severity is seen. Due to a large allelic heterogeneity, establishing genotype-phenotype correlations is difficult. However, reliable prediction of the natural course of the disease is needed, in particular for the assessment of the efficacy of potential therapies. To identify markers that correlate with disease severity, all Dutch patients diagnosed with MPS IIIB were characterised as either rapid (RP; classical, severe phenotype) or slow progressors (SP; non-classical, less severe phenotype), based on clinical data. NAGLU activity and HS levels were measured in patients' fibroblasts after culturing at different temperatures. A small, though significant difference in NAGLU activity was ...

Research paper thumbnail of Post-zygotic mutations and somatic mosaicism in androgen insensitivity syndrome

Trends in Genetics, 2001

Holterhus et al. (this issue) correctly point out that we did indeed misinterpret part of their r... more Holterhus et al. (this issue) correctly point out that we did indeed misinterpret part of their results concerning the possibility that some cases of androgen insensitivity syndrome (AIS) could be due to somatic mosaicism caused by the back mutation of mutant androgen receptors to wild-type in some androgen responsive tissues. However, although back mutations have not yet been proven to be a source of somatic mosaicism in cases of AIS, there are a number of other cases in the literature where back mutations do indeed result in somatic mosaicism1xReverse mutations – spontaneous amelioration or cure of inherited disorders?. Wahn, V. et al. Eur. J. Pediatr. 1998; 157: 613–617Crossref | PubMed | Scopus (6)See all References, 2xRevertant mosaicism in human genetic disorders. Jonkman, M.F. Am. J. Med. Genet. 1999; 85: 361–364Crossref | PubMed | Scopus (34)See all References, 3xBack mutations can produce phenotype reversion in Bloom syndrome somatic cells. Ellis, N.A. et al. Hum. Genet. 2001; 108: 167–173Crossref | PubMed | Scopus (20)See all References.We are also grateful that they chose to reinforce the importance of such information for genetic counseling, particularly because the occurrence of somatic mosaicism has recently been shown to be more than just an isolated series of events in a number of genetic disorders. In these conditions, which include hemophilia A (Ref. 4xSomatic mosaicism in Hemophilia A: a fairly common event. Leuer, M. et al. Am. J. Hum. Genet. 2001; 69: 75–87Abstract | Full Text | Full Text PDF | PubMed | Scopus (83)See all ReferencesRef. 4), hemophilia B (Ref. 5xGermline origins in the human F9 gene: frequent G:C(A:T mosaicism and increased mutations with advanced maternal age. Ketterling, R.P. et al. Hum. Genet. 1999; 105: 629–640Crossref | PubMed | Scopus (30)See all ReferencesRef. 5), retinoblastoma6xFrequency of somatic and germ-line mosaicism in Retinoblastoma: implications for genetic counseling. Sippel, K.C. et al. Am. J. Hum. Genet. 1998; 62: 610–619Abstract | Full Text | Full Text PDF | PubMed | Scopus (106)See all References6 and tuberous sclerosis complex7xHigh rate of mosaicism in tuberous sclerosis complex. Verhoef, S. et al. Am. J. Hum. Genet. 1999; 64: 1632–1637Abstract | Full Text | Full Text PDF | PubMed | Scopus (99)See all References7, somatic mosaicism can occur at a frequency of 10–20%. Furthermore, these studies also note that somatic mosaicism is a possible source not only of variable expressivity, but also of altered penetrance.These observations add weight to our hypothesis that, with the recently acquired ability to sequence specific tissues easily and efficiently, somatic mosaicism is increasingly likely to be observed as a source of variable expressivity in many disorders and diseases.

Research paper thumbnail of HLA frequencies and associations in cystic fibrosis

Tissue Antigens, 2013

Cystic fibrosis (CF) is classically attributed to the dysfunction of the single CF transmembrane ... more Cystic fibrosis (CF) is classically attributed to the dysfunction of the single CF transmembrane conductance regulator gene. The incidence of human leukocyte antigen (HLA) polymorphisms in different CF-associated diseases raises the question of an unequal distribution of HLA genotypes in CF. This study aimed to evaluate HLA gene frequencies and possible associations in CF patients compared with a control population. Frequencies of HLA-DRB1, HLA-DQA1 and HLA-DQB1, performed by intermediate resolution typing using Luminex sequence-specific oligonucleotide, and epitope counts were similar in 340 CF patients when compared with 400 control subjects. In conclusion, HLA-DRB1,-DQA1 and-DQB1 do not seem to influence susceptibility to CF. Whether HLA plays a role in the severity of CF disease needs to be investigated.

Research paper thumbnail of Differential diagnosis in spinal and bulbar muscular atrophy clinical and molecular aspects

Journal of the Neurological Sciences, 1995

Kennedy disease is caused by an enlarged trinucleotide repeat sequence within the androgen recept... more Kennedy disease is caused by an enlarged trinucleotide repeat sequence within the androgen receptor gene. We report here seven male patients with a benign motor neuron syndrome highly analogous to Kennedy disease but with a normal trinucleotide repeat.

Research paper thumbnail of Advanced Pubertal Development in Two Adolescents with New SF-1 Mutations

Journal of Pediatric Urology, 2010

The cosmetic results of reconstructive surgery for girls with congenital adrenal hyperplasia have... more The cosmetic results of reconstructive surgery for girls with congenital adrenal hyperplasia have improved significantly over the past two decades. However, one component that is less than perfect is the appearance of the clitoris, particularly its dorsal skin cover. This presentation describes an approach to managing the dorsal skin cover that consistently results in a naturally hooded clitoris and reduces the need for excisional reduction of the size of the glans clitoris except in the severely hypertrophied cases. MATERIAL AND METHODS Rather than separate the dorsal mucosal attachments to the glans clitoris, they are left intact and the circumferential skin incision is shifted proximally, at the point which would form the base of the reduced clitoral shaft. The shaft skin proximal to that is split in the midline and used for construction of the labia minora. And the circumscribing incision is sutured to the apex of the midline dorsal incision. RESULTS This procedure has been used successfully in 3 patients with excellent intermediate results (6-12 months).The clitoris retained a natural position and hooded appearance. There was no cross healing or other complications.

Research paper thumbnail of Mosaicism due to a Somatic Mutation of the Androgen Receptor Gene Determines Phenotype in Androgen Insensitivity Syndrome1

The Journal of Clinical Endocrinology & Metabolism, 1997

Premature stop codons of the human androgen receptor (AR) gene are usually associated with a comp... more Premature stop codons of the human androgen receptor (AR) gene are usually associated with a complete androgen insensitivity syndrome. We, however, identified an adult patient with a 46,XY karyotype carrying a premature stop codon in exon 1 of the AR gene presenting with signs of partial virilization: pubic hair Tanner stage 4 and clitoral enlargement. No other family members were affected. A point mutation at codon position 172 of the AR gene was detected that replaced the original TTA (Leu) with a premature stop codon TGA (opal). Careful examination of the sequencing gel, however, also identified a wild-type allele, indicating a mosaicism. In addition, elimination of the unique AflII recognition site induced by the mutation was incomplete, thus confirming the coexistence of mutant and wild-type AR alleles in the patient. Normal R1881 binding and a normal 110/112-kDa AR doublet in Western immunoblots consolidated the molecular genetic data by demonstrating the expression of the wil...

Research paper thumbnail of Gene Expression Profiling in Uveal Melanoma: Two Regions on 3p Related to Prognosis

Investigative Opthalmology & Visual Science, 2008

PURPOSE. Although studies on uveal melanoma (UM) revealed prognostic significance of chromosomal ... more PURPOSE. Although studies on uveal melanoma (UM) revealed prognostic significance of chromosomal aberrations, they resulted in classification errors in survival prediction. A robust prognostic classifier with strong predictive value and further insight in genes responsible for poor prognosis were obtained by performing a gene-expression profile in tumors of UM patients for which extensive clinical, histopathologic, cytogenetic, and follow-up data were available. Furthermore, the UM microarray expression data were compared with cytogenetic data. METHODS. Gene-expression profiles of 46 UMs were obtained with microchip assays. Data were analyzed with cluster-analysis and predictive analysis of microarrays (PAM) software and validated with real-time PCR. The prognostic significance of UMs with specific molecular signatures was determined. Furthermore, LAP analysis resulted in the identification of differentially expressed chromosomal regions. RESULTS. The primary UMs were classified in two distinct molecular classes with a strong prognostic value (P Ͻ 0.001; hazard ratio 7.7). Classifier gene sets for microarray class and disease-free survival were validated with real-time PCR, and the predictive value of the UM class marker set was validated with gene-expression profiles of tumors provided by other institutions, showing a sensitivity of 0.93 and specificity of 1.00 for class II tumors. A locally adaptive statistical procedure identified two regions on the short arm of chromosome 3 with decreased gene-expression in tumors with shorter disease-free survival. CONCLUSIONS. Microarray classification outperforms known prognostic indicators for UM, such as clinical, histopathologic, and cytogenetic parameters. In addition, the identified regions with lower expressed genes on 3p could harbor genes that are responsible for the poor prognosis of patients with UM.

Research paper thumbnail of A DGGE system for comprehensive mutation screening ofBRCA1andBRCA2: application in a Dutch cancer clinic setting

Human Mutation, 2006

Communicated by Dvorah Abeliovich Rapid and reliable identification of deleterious changes in the... more Communicated by Dvorah Abeliovich Rapid and reliable identification of deleterious changes in the breast cancer genes BRCA1 and BRCA2 has become one of the major issues in most DNA services laboratories. To rapidly detect all possible changes within the coding and splice site determining sequences of the breast cancer genes, we established a semiautomated denaturing gradient gel electrophoresis (DGGE) mutation scanning system. All exons of both genes are covered by the DGGE scan, comprising 120 amplicons. We use a semiautomated approach, amplifying all individual amplicons with the same PCR program, after which the amplicons are pooled. DGGE is performed using three slightly different gel conditions. Validation was performed using DNA samples with known sequence variants in 107 of the 120 amplicons; all variants were detected. This DGGE mutation scanning, in combination with a PCR test for two Dutch founder deletions in BRCA1 was then applied in 431 families in which 52 deleterious changes and 70 unclassified variants were found. Fifteen unclassified variants were not reported before. The system was easily adopted by five other laboratories, where in another 3,593 families both exons 11 were analyzed by the protein truncation test (PTT) and the remaining exons by DGGE. In total, a deleterious change (nonsense, frameshift, splice-site mutation, or large deletion) was found in 661 families (16.4%), 462 in BRCA1 (11.5%), 197 in BRCA2 (4.9%), and in two index cases a deleterious change in both BRCA1 and BRCA2 was identified. Eleven deleterious changes in BRCA1 and 36 in BRCA2 had not been reported before. In conclusion, this DGGE mutation screening method for BRCA1 and BRCA2 is proven to be highly sensitive and is easy to adopt, which makes screening of large numbers of patients feasible. The results of screening of BRCA1 and BRCA2 in more than 4,000 families present a valuable overview of mutations in the Dutch population.

Research paper thumbnail of Survival and prognostic factors in BRCA1-associated breast cancer

Annals of Oncology, 2006

Studies comparing survival in BRCA1-associated and sporadic breast cancer (BC) report inconsisten... more Studies comparing survival in BRCA1-associated and sporadic breast cancer (BC) report inconsistent results and frequently concern small sample sizes. Further, the prognostic impact of the classical tumour and treatment factors is unclear in BRCA1-associated BC. We selected 223 BC patients diagnosed between 1980 and 2001 within families with a deleterious germline BRCA1-mutation ascertained at the Rotterdam Family Cancer Clinic. To correct for ascertainment bias, the group of index patients undergoing DNA testing more than 2 years after BC diagnosis (n = 53) was separated from the other BRCA1-patients (n = 170). All BRCA1-associated patients were matched in a 1:2 ratio for age and year of diagnosis to sporadic BC patients. We compared the occurrence of ipsi- and contralateral BC (CBC) as well as distant disease-free (DDFS), BC-specific (BCSS) and overall survival (OS). By multivariate modelling, the prognostic impact of tumour and treatment factors was investigated separately in BRCA1-associated and sporadic breast cancers. For the total group of 669 cases, the median follow-up was 5.1 years, the median age at diagnosis 39 years. We confirmed the existence of the typical BRCA1-associated tumour type and the high CBC incidence. No significant differences between BRCA1-associated and sporadic tumours were found with respect to ipsilateral BC recurrence (HR(mult) 0.7; P = 0.24), DDFS (HR(mult) 1.2; P = 0.37) or BC-specific survival (HR(mult) 1.3; P = 0.23). A trend towards a worse survival was found for BRCA1-associated ductal BC (HR(mult) 1.5, P = 0.07). Prognostic factors for BRCA1-associated BC were age at diagnosis, tumour size and morphology, and nodal status. Further, survival was non-significantly improved by systemic treatment and a bilateral salpingo-oophorectomy. No effect on survival of a contralateral prophylactic mastectomy was seen. BRCA1-associated BC is characterised by specific tumour characteristics, a high incidence of CBC and a trend towards a worse survival for the ductal tumour type. Our observation that tumour size and nodal status are also prognostic factors for BRCA1-associated BC implies that the strategy to use these factors as a proxy for ultimate mortality, for instance in BC screening programmes or the consideration of (contralateral) preventive mastectomy, appears to be valid in this specific group of patients.

Research paper thumbnail of Anticipation resulting in elimination of the myotonic dystrophy gene: a follow up study of one extended family

Journal of Medical Genetics, 1994

Research paper thumbnail of Molecular Analysis of the Androgen-Receptor Gene in a Family with Receptor-Positive Partial Androgen Insensitivity: An Unusual Type of Intronic Mutation

The American Journal of Human Genetics, 1997

In the coding part and the intron-exon boundaries of the androgen-receptor gene of a patient with... more In the coding part and the intron-exon boundaries of the androgen-receptor gene of a patient with partial androgen insensitivity, no mutation was found. The androgen receptor of this patient displayed normal ligand-binding parameters and migrated as a 110-112-kD doublet on SDS-PAGE in the absence of hormone. However, after culturing of the patient's genital skin fibroblasts in the presence of hormone, the slowermigrating 114-kD protein, which reflects hormonedependent phosphorylation, was hardly detectable. Furthermore, receptor protein was undetectable in the nuclear fraction of the fibroblasts, after treatment with hormone, which is indicative of defective DNA binding. By sequencing part of intron 2, a TrA mutation was found 11 bp upstream of exon 3. In our screening of 102 chromosomes from unrelated individuals, this basepair substitution was not found, indicating that it was not a polymorphism. mRNA analysis revealed that splicing involved a cryptic splice site, located 71/70 bp upstream of exon 3, resulting in generation of mRNA with an insert of 69 nucleotides. In addition, a small amount of a transcript with a deleted exon 3 and a very low level of wild-type transcript were detected. Translation of the extended transcript resulted in an androgen-receptor protein with 23 amino acid residues inserted between the two zinc clusters, displaying defective DNA binding and defective transcription activation.

Research paper thumbnail of A NovelAMHMissense Mutation in a Patient with Persistent Müllerian Duct Syndrome

Sexual Development, 2012

external genitalia under influence of hormones produced by the gonads [Wilhelm et al., 2007; Fran... more external genitalia under influence of hormones produced by the gonads [Wilhelm et al., 2007; Franco and Yao, 2012]. Testosterone produced by testicular Leydig cells will induce the differentiation of the male reproductive tract, i.e. the Wolffian ducts, into epididymis, vas deferens, and seminal vesicles. Anti-Müllerian hormone (AMH), produced by the testicular Sertoli cells, is responsible for the regression of the Müllerian ducts. In the absence of AMH the Müllerian ducts will develop into normal female internal organs [Behringer et al., 1994]. Persistent Müllerian duct syndrome (PMDS) is characterized by the presence of a uterus, fallopian tubes and the upper part of the vagina in phenotypic normal male patients, and is usually discovered at surgery for cryptorchidism or inguinal hernias. AMH, a member of the transforming growth factor ␤ (TGF ␤) family, signals through a heterodimeric receptor complex consisting of a specific type II receptor (AMHRII) and shared type I receptors (ALK2, 3, and 6) [Visser, 2003; Orvis et al., 2008]. In approximately 85% of the cases mutations within the AMH and AMHR2 genes are responsible for this error in sex differentiation [Josso et al., 2005]. Mutations in the 3 type I receptor genes have not been detected [Josso et al., 2005], and thus for the remaining 15% of the cases the causative genes remain to be identified. Patients with mutations in