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Papers by Judith Fischer

Frontiers in Genetics, 2021

Neonatal collodion baby or ichthyosis can pose a diagnostic challenge, and in many cases, only ad... more Neonatal collodion baby or ichthyosis can pose a diagnostic challenge, and in many cases, only additional organ involvement or the course of the disease will help differentiate between non-syndromic and syndromic forms. Skin abnormalities are described in about 20% of the congenital disorders of glycosylation (CDG). Among those, some rare CDG forms constitute a special group among the syndromic ichthyoses and can initially misdirect the diagnosis towards non-syndromic genodermatosis. DOLK-CDG is such a rare subtype, resulting from a defect in dolichol kinase, in which the congenital skin phenotype (often ichthyosis) is later associated with variable extracutaneous features such as dilatative cardiomyopathy, epilepsy, microcephaly, visual impairment, and hypoglycemia and may lead to a fatal course. We report two neonatal cases of lethal ichthyosis from the same family, with distal digital constrictions and a progressive course leading to multi-organ failure and death. Postmortem trio...

American journal of human genetics, 2017

Ichthyoses are a clinically and genetically heterogeneous group of genodermatoses associated with... more Ichthyoses are a clinically and genetically heterogeneous group of genodermatoses associated with abnormal scaling of the skin over the whole body. Mutations in nine genes are known to cause non-syndromic forms of autosomal-recessive congenital ichthyosis (ARCI). However, not all genetic causes for ARCI have been discovered to date. Using whole-exome sequencing (WES) and multigene panel screening, we identified 6 ARCI-affected individuals from three unrelated families with mutations in Sulfotransferase family 2B member 1 (SULT2B1), showing their causative association with ARCI. Cytosolic sulfotransferases form a large family of enzymes that are involved in the synthesis and metabolism of several steroids in humans. We identified four distinct mutations including missense, nonsense, and splice site mutations. We demonstrated the loss of SULT2B1 expression at RNA and protein levels in keratinocytes from individuals with ARCI by functional analyses. Furthermore, we succeeded in reconst...

Human Mutation, Mar 1, 2013

Missense mutations affecting membrane-bound transcription factor protease site 2 (MBTPS2) have be... more Missense mutations affecting membrane-bound transcription factor protease site 2 (MBTPS2) have been associated with Ichthyosis Follicularis with Atrichia and Photophobia (IFAP) syndrome with or without BRESHECK syndrome, with keratosis follicularis spinulosa decalvans, and Olmsted syndrome. This metalloprotease activates, by intramembranous trimming in conjunction with the protease MBTPS1, regulatory factors involved in sterol control of transcription and in cellular stress response. In this study, 11 different MBTPS2 missense mutations detected in patients from 13 unrelated families were correlated with the clinical phenotype, with their effect on cellular growth in media without lipids, and their potential role for sterol control of transcription. Seven variants were novel [c.774C>G (p.I258M); c.758G>C (p.G253A); c.686T>C (p.F229S); c.1427T>C (p.L476S); c.1430A>T (p.D477V);…

Molecular Genetics & Genomic Medicine

BackgroundNetherton syndrome (NS) is a genodermatosis caused by loss‐of‐function mutations in SPI... more BackgroundNetherton syndrome (NS) is a genodermatosis caused by loss‐of‐function mutations in SPINK5, resulting in aberrant LEKTI expression.MethodNext‐generation sequencing of SPINK5 (NM_001127698.1) was carried out and functional studies were performed by immunofluorescence microscopy of a lesional skin biopsy using anti‐LEKTI antibodies.ResultsWe describe a novel SPINK5 likely pathogenic donor splice site variant (NM_001127698.1:c.2015+5G>A) in a patient with NS and confirm its functional significance by demonstrating complete loss of LEKTI expression in lesional skin by immunofluorescence analysis.ConclusionThe 2015+5G>A is a novel, likely pathogenic variant in NS. Herein we review and assimilate documented SPINK5 pathogenic variants and discuss possible genotype–phenotype associations in NS.

British Journal of Dermatology

Background A trio exome sequencing study identified a previously unreported NLRP1 gene variant re... more Background A trio exome sequencing study identified a previously unreported NLRP1 gene variant resulting in a p.Leu813Pro substitution of the LRR (leucine-rich repeats) domain of the NLRP1 protein (NACHT, LRR and PYD domains-containing protein 1). This homozygous mutation was shared by two sisters with different clinical presentation: the younger sister had generalized inflammatory nodules with keratotic plugs, clinically resembling multiple keratoacanthomas, while the older had manifestations of familial keratosis lichenoides chronica. Objectives To analyse the consequences of this NLRP1 variant in two siblings with a different clinical spectrum of severity. Methods To demonstrate the pathogenicity, p.Leu813Pro was recombinantly expressed, and its effect on inflammasome assembly was assessed. Exome sequencing and RNA-Seq were performed to identify factors with potentially modifying effects on the severity of the skin manifestation between each sibling. Results The variant p.Leu813P...

Frontiers in Immunology

Inherited defects in MyD88 and IRAK4, two regulators in Toll-like receptor (TLR) signaling, are c... more Inherited defects in MyD88 and IRAK4, two regulators in Toll-like receptor (TLR) signaling, are clinically highly relevant, but still incompletely understood. MyD88- and IRAK4-deficient patients are exceedingly susceptible to a narrow spectrum of pathogens, with ∼50% lethality in the first years of life. To better understand the underlying molecular and cellular characteristics that determine disease progression, we aimed at modeling the cellular response to pathogens in vitro. To this end, we determined the immunophenotype of monocytes and macrophages derived from MyD88- and IRAK4-deficient patients. We recognized that macrophages derived from both patients were particularly poorly activated by streptococci, indicating that both signaling intermediates are essential for the immune response to facultative pathogens. To characterize this defect in more detail, we generated induced pluripotent stem cells (iPSCs) of fibroblasts derived from an MyD88-deficient patient. The underlying ge...

BMC Medical Genomics, 2022

Background Ichthyosis is a heterogeneous group of Mendelian cornification disorders that includes... more Background Ichthyosis is a heterogeneous group of Mendelian cornification disorders that includes syndromic and non-syndromic forms. Autosomal Recessive Congenital Ichthyosis (ARCI) and Ichthyosis Linearis Circumflexa (ILC) belong to non-syndromic forms. Syndromic ichthyosis is rather a large group of heterogeneous diseases. Overlapping phenotypes and genotypes between these disorders is a major characteristic. Therefore, determining the specific genetic background for each form would be necessary. Methods A total of 11 Tunisian patients with non-syndromic (8 with ARCI and 2 with ILC) and autosomal syndromic ichthyosis (1 patient) were screened by a custom Agilent HaloPlex multi-gene panel and the segregation of causative mutations were analyzed in available family members. Results Clinical and molecular characterization, leading to genotype–phenotype correlation in 11 Tunisian patients was carried out. Overall, we identified 8 mutations in 5 genes. Thus, in patients with ARCI, we i...

JDDG: Journal der Deutschen Dermatologischen Gesellschaft, 2021

Acta Dermato Venereologica, 2020

Fig. 1. (a-c) Representative lesions of sebaceous naevus and papular naevi spili in a 41-year-old... more Fig. 1. (a-c) Representative lesions of sebaceous naevus and papular naevi spili in a 41-year-old patient with phacomatosis pigmentokeratotica. (d) Squamous cell carcinoma in the naevus sebaceous on the scalp with regional nodal metastasis.

Annales de Dermatologie et de Vénéréologie, 2019

Journal of Investigative Dermatology, 2019

Brooke-Spiegler syndrome (BSS; OMIM 605041) is a rare monogenic skin disease characterized by the... more Brooke-Spiegler syndrome (BSS; OMIM 605041) is a rare monogenic skin disease characterized by the development of skin appendage tumors caused by mutations in the cylindromatosis gene (CYLD). Concerning the so far reported phenotypes and the underlying CYLD mutations, it is difficult to establish genotype-phenotype correlations in BSS. We have recently investigated a Hungarian family (with Bukovinian origin) and an Anglo-Saxon BSS pedigree, in whom the affected family members-despite of carrying the same diseasecausing mutation (c.2806C>T, p.Arg936X) of the CYLD gene-show striking differences in their phenotypes. The aim of our study was to identify phenotype modifier genetic factors, which could help the understanding of genotype-phenotype correlations in BSS. Comparing the WES data of the Hungarian and Anglo-Saxon BSS patients, here we have identified three putative phenotype modifying genetic variants: the rs1053023 SNP of the signal transducer and activator of transcription 3 (STAT3) gene, the rs1131877 SNP of the tumor necrosis factor receptor-associated factor 3 (TRAF3) gene and the rs202122812 SNP of the neighbor of BRCA1 gene 1 (NBR1) gene. Our study contributes to the accumulating evidence describing the clinical importance of genetic phenotype modifying factors, which have high potential in the elucidation of genotype-phenotype correlations and disease prognosis.

Frontiers in Neurology, 2019

Chorea-acanthocytosis (ChAc) is a rare, adult-onset disease usually characterized by, hence the n... more Chorea-acanthocytosis (ChAc) is a rare, adult-onset disease usually characterized by, hence the name, a movement disorder and acanthocytosis in the blood. It is caused by mutations of the VPS13A gene with an autosomal recessive transmission. We report a consanguineous Turkish family with a different and informative clinical and diagnostic course. Three siblings developed seizures and the index patient had been diagnosed with bilateral temporal lobe epilepsy. A key finding, however, was the basal ganglia involvement in neuroimaging although no movement disorder was present. [ 18 F]FDG-PET showed a prominent decline in striatal glucose metabolism at 31 years of age and [ 123 I]FP-CIT-SPECT revealed a moderate loss of striatal dopamine transporter availability. The family was referred for genetic testing and exome sequencing detected a homozygous novel truncating mutation c.4326 T>A (p.Tyr1442 *) in VPS13A in all affected siblings. With this case, we present autosomal recessive epilepsy as the predominant phenotype of ChAc with a new homozygous VPS13A mutation and provide pathological structural and molecular neuroimaging findings.

British Journal of Dermatology, 2018

Go to publication entry in University of Southern Denmark's Research Portal Terms of use This wor... more Go to publication entry in University of Southern Denmark's Research Portal Terms of use This work is brought to you by the University of Southern Denmark. Unless otherwise specified it has been shared according to the terms for self-archiving. If no other license is stated, these terms apply: • You may download this work for personal use only. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying this open access version If you believe that this document breaches copyright please contact us providing details and we will investigate your claim.

Journal of Biological Chemistry, 2008

Adipose triglyceride lipase (ATGL) catalyzes the first step in the hydrolysis of triacylglycerol ... more Adipose triglyceride lipase (ATGL) catalyzes the first step in the hydrolysis of triacylglycerol (TG) generating diacylglycerol and free fatty acids. The enzyme requires the activator protein CGI-58 (or ABHD5) for full enzymatic activity. Defective ATGL function causes a recessively inherited disorder named neutral lipid storage disease that is characterized by systemic TG accumulation and myopathy. In this study, we investigated the functional defects associated with mutations in the ATGL gene that cause neutral lipid storage disease. We show that these mutations lead to the expression of either inactive enzymes localizing to lipid droplets (LDs) or enzymatically active lipases with defective LD binding. Additionally, our studies assign important regulatory functions to the C-terminal part of ATGL. Truncated mutant ATGL variants lacking ϳ220 amino acids of the C-terminal protein region do not localize to LDs. Interestingly, however, these mutants exhibit substantially increased TG hydrolase activity in vitro (up to 20-fold) compared with the wild-type enzyme, indicating that the C-terminal region suppresses enzyme activity. Protein-protein interaction studies revealed an increased binding of truncated ATGL to CGI-58, suggesting that the C-terminal part interferes with CGI-58 interaction and enzyme activation. Compared with the human enzyme, the C-terminal region of mouse ATGL is much less effective in suppressing enzyme activity, implicating species-dependent differences in enzyme regulation. Together, our results demonstrate that the C-terminal region of ATGL is essential for proper localization of the enzyme and suppresses enzyme activity. Adipose triglyceride lipase (ATGL; official gene symbol: PNPLA2, patatin-like phospholipase domain containing 2) 3 is * This work was supported by Grant P18434-B05 from the Austrian Fonds zur Fö rderung der wissenschaftlichen Forschung and "GOLD-Genomics of Lipid-Associated Disorders," which is part of the Austrian Genome Project "GEN-AU Genome Research in Austria" and is funded by the Austrian Ministry for Education, Research, and Culture.

Acta Dermato Venereologica, 2020

This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Acta Derm ... more This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Acta Derm Venereol 2020; 100: adv00096 Centenary theme section: GENODERMATOSES SIGNIFICANCE Knowledge of the molecular genetic causes and mechanisms of hereditary ichthyoses has increased hugely since the 1990s due to the ubiquitous application of modern sequencing technologies. It is important for doctors and scientists that this new knowledge is clinically and genetically correctly classified, in order to make diagnosis and differential diagnosis easier. This article provides an overview of the genetic background and clinical features of ichthyoses and related cornification disorders. Inherited ichthyoses are classified as Mendelian disorders of cornification (MEDOC), which are defined on the basis of clinical and genetic features and are mainly divided into non-syndromic and syndromic ichthyoses. Numerous genes, which encode for corresponding proteins, are involved in the normal differentiation of keratinocytes (cornification) and participate in the formation of a functional epidermal barrier. To date, mutations in more than 50 genes are known to result in various types of ichthyoses. Thanks to modern genetic diagnostic methods based on targeted next generation sequencing (NGS), approximately 80-90% of cases can be resolved at present. Further sequencing methods covering the whole exome (WES) or whole genome (WGS) will obviously elucidate another portion of the remaining unknown ichthyoses in the future.

Genes

Autosomal recessive congenital ichthyosis (ARCI) is a non-syndromic congenital disorder of cornif... more Autosomal recessive congenital ichthyosis (ARCI) is a non-syndromic congenital disorder of cornification characterized by abnormal scaling of the skin. The three major phenotypes are lamellar ichthyosis, congenital ichthyosiform erythroderma, and harlequin ichthyosis. ARCI is caused by biallelic mutations in ABCA12, ALOX12B, ALOXE3, CERS3, CYP4F22, NIPAL4, PNPLA1, SDR9C7, SULT2B1, and TGM1. The most severe form of ARCI, harlequin ichthyosis, is caused by mutations in ABCA12. Mutations in this gene can also lead to congenital ichthyosiform erythroderma or lamellar ichthyosis. We present a large cohort of 64 patients affected with ARCI carrying biallelic mutations in ABCA12. Our study comprises 34 novel mutations in ABCA12, expanding the mutational spectrum of ABCA12-associated ARCI up to 217 mutations. Within these we found the possible mutational hotspots c.4541G>A, p.(Arg1514His) and c.4139A>G, p.(Asn1380Ser). A correlation of the phenotype with the effect of the genetic muta...

British Journal of Dermatology

medizinische genetik, 2019

ZusammenfassungEpidermolysis bullosa hereditaria (EB) umfasst eine Gruppe von Erkrankungen, die m... more ZusammenfassungEpidermolysis bullosa hereditaria (EB) umfasst eine Gruppe von Erkrankungen, die mit Hautfragilität und mechanisch verursachter Blasenbildung einhergehen. Die klinischen Manifestationen zeigen unterschiedliche Schweregrade, von lebensbedrohlich bis leicht. Im Kindesalter und bei Erwachsenen kann das klinische Bild typisch sein; allerdings kann bei Neugeborenen der EB-Subtyp klinisch häufig nicht bestimmt werden. Pathogene Varianten in 20 Genen sind bereits als krankheitsursächlich für die verschiedenen Formen der EB beschrieben. Die allelische Heterogenität ist sehr groß. Die Diagnostik basiert auf der genauen klinischen Untersuchung, der Familienanamnese und der molekulargenetischen Analyse. Aufgrund der genetischen Heterogenität und der Größe der Gene eignet sich die „Next-generation-sequencing“-basierte Multi-Gen-Panel-Diagnostik am besten. Teilweise sind Genotyp-Phänotyp-Korrelationen bekannt, sodass die genetische Diagnostik auch prognostisch eine Rolle spielt.

American Journal of Medical Genetics Part A, 2005

British Journal of Dermatology

Background Hyperkeratosis lenticularis perstans (HLP), also known as Flegel disease, is a rare sk... more Background Hyperkeratosis lenticularis perstans (HLP), also known as Flegel disease, is a rare skin disease presenting with asymptomatic small hyperkeratotic papules. The lesions often appear on the dorsal feet and lower legs, and typically develop after the fourth decade of life. A genetic basis for HLP is suspected; however, so far no gene defect linked to the development of HLP has been identified. Objectives We aimed to identify the genetic cause of HLP. Methods For mutational analysis we studied a cohort of five patients with HLP using next-generation sequencing (NGS). We used DNA ­extracted from fresh skin biopsies alongside ethylenediamine tetraacetic acid (EDTA) blood samples from two patients, and formalin-fixed ­paraffin-embedded skin biopsy material from three patients. In addition, immunofluorescence staining of HLP lesions from four patients was investigated. Results In all samples from the five patients with HLP we identified by NGS rare variants in the SPTLC1 gene. In...

Frontiers in Genetics, 2021

Neonatal collodion baby or ichthyosis can pose a diagnostic challenge, and in many cases, only ad... more Neonatal collodion baby or ichthyosis can pose a diagnostic challenge, and in many cases, only additional organ involvement or the course of the disease will help differentiate between non-syndromic and syndromic forms. Skin abnormalities are described in about 20% of the congenital disorders of glycosylation (CDG). Among those, some rare CDG forms constitute a special group among the syndromic ichthyoses and can initially misdirect the diagnosis towards non-syndromic genodermatosis. DOLK-CDG is such a rare subtype, resulting from a defect in dolichol kinase, in which the congenital skin phenotype (often ichthyosis) is later associated with variable extracutaneous features such as dilatative cardiomyopathy, epilepsy, microcephaly, visual impairment, and hypoglycemia and may lead to a fatal course. We report two neonatal cases of lethal ichthyosis from the same family, with distal digital constrictions and a progressive course leading to multi-organ failure and death. Postmortem trio...

American journal of human genetics, 2017

Ichthyoses are a clinically and genetically heterogeneous group of genodermatoses associated with... more Ichthyoses are a clinically and genetically heterogeneous group of genodermatoses associated with abnormal scaling of the skin over the whole body. Mutations in nine genes are known to cause non-syndromic forms of autosomal-recessive congenital ichthyosis (ARCI). However, not all genetic causes for ARCI have been discovered to date. Using whole-exome sequencing (WES) and multigene panel screening, we identified 6 ARCI-affected individuals from three unrelated families with mutations in Sulfotransferase family 2B member 1 (SULT2B1), showing their causative association with ARCI. Cytosolic sulfotransferases form a large family of enzymes that are involved in the synthesis and metabolism of several steroids in humans. We identified four distinct mutations including missense, nonsense, and splice site mutations. We demonstrated the loss of SULT2B1 expression at RNA and protein levels in keratinocytes from individuals with ARCI by functional analyses. Furthermore, we succeeded in reconst...

Human Mutation, Mar 1, 2013

Missense mutations affecting membrane-bound transcription factor protease site 2 (MBTPS2) have be... more Missense mutations affecting membrane-bound transcription factor protease site 2 (MBTPS2) have been associated with Ichthyosis Follicularis with Atrichia and Photophobia (IFAP) syndrome with or without BRESHECK syndrome, with keratosis follicularis spinulosa decalvans, and Olmsted syndrome. This metalloprotease activates, by intramembranous trimming in conjunction with the protease MBTPS1, regulatory factors involved in sterol control of transcription and in cellular stress response. In this study, 11 different MBTPS2 missense mutations detected in patients from 13 unrelated families were correlated with the clinical phenotype, with their effect on cellular growth in media without lipids, and their potential role for sterol control of transcription. Seven variants were novel [c.774C>G (p.I258M); c.758G>C (p.G253A); c.686T>C (p.F229S); c.1427T>C (p.L476S); c.1430A>T (p.D477V);…

Molecular Genetics & Genomic Medicine

BackgroundNetherton syndrome (NS) is a genodermatosis caused by loss‐of‐function mutations in SPI... more BackgroundNetherton syndrome (NS) is a genodermatosis caused by loss‐of‐function mutations in SPINK5, resulting in aberrant LEKTI expression.MethodNext‐generation sequencing of SPINK5 (NM_001127698.1) was carried out and functional studies were performed by immunofluorescence microscopy of a lesional skin biopsy using anti‐LEKTI antibodies.ResultsWe describe a novel SPINK5 likely pathogenic donor splice site variant (NM_001127698.1:c.2015+5G>A) in a patient with NS and confirm its functional significance by demonstrating complete loss of LEKTI expression in lesional skin by immunofluorescence analysis.ConclusionThe 2015+5G>A is a novel, likely pathogenic variant in NS. Herein we review and assimilate documented SPINK5 pathogenic variants and discuss possible genotype–phenotype associations in NS.

British Journal of Dermatology

Background A trio exome sequencing study identified a previously unreported NLRP1 gene variant re... more Background A trio exome sequencing study identified a previously unreported NLRP1 gene variant resulting in a p.Leu813Pro substitution of the LRR (leucine-rich repeats) domain of the NLRP1 protein (NACHT, LRR and PYD domains-containing protein 1). This homozygous mutation was shared by two sisters with different clinical presentation: the younger sister had generalized inflammatory nodules with keratotic plugs, clinically resembling multiple keratoacanthomas, while the older had manifestations of familial keratosis lichenoides chronica. Objectives To analyse the consequences of this NLRP1 variant in two siblings with a different clinical spectrum of severity. Methods To demonstrate the pathogenicity, p.Leu813Pro was recombinantly expressed, and its effect on inflammasome assembly was assessed. Exome sequencing and RNA-Seq were performed to identify factors with potentially modifying effects on the severity of the skin manifestation between each sibling. Results The variant p.Leu813P...

Frontiers in Immunology

Inherited defects in MyD88 and IRAK4, two regulators in Toll-like receptor (TLR) signaling, are c... more Inherited defects in MyD88 and IRAK4, two regulators in Toll-like receptor (TLR) signaling, are clinically highly relevant, but still incompletely understood. MyD88- and IRAK4-deficient patients are exceedingly susceptible to a narrow spectrum of pathogens, with ∼50% lethality in the first years of life. To better understand the underlying molecular and cellular characteristics that determine disease progression, we aimed at modeling the cellular response to pathogens in vitro. To this end, we determined the immunophenotype of monocytes and macrophages derived from MyD88- and IRAK4-deficient patients. We recognized that macrophages derived from both patients were particularly poorly activated by streptococci, indicating that both signaling intermediates are essential for the immune response to facultative pathogens. To characterize this defect in more detail, we generated induced pluripotent stem cells (iPSCs) of fibroblasts derived from an MyD88-deficient patient. The underlying ge...

BMC Medical Genomics, 2022

Background Ichthyosis is a heterogeneous group of Mendelian cornification disorders that includes... more Background Ichthyosis is a heterogeneous group of Mendelian cornification disorders that includes syndromic and non-syndromic forms. Autosomal Recessive Congenital Ichthyosis (ARCI) and Ichthyosis Linearis Circumflexa (ILC) belong to non-syndromic forms. Syndromic ichthyosis is rather a large group of heterogeneous diseases. Overlapping phenotypes and genotypes between these disorders is a major characteristic. Therefore, determining the specific genetic background for each form would be necessary. Methods A total of 11 Tunisian patients with non-syndromic (8 with ARCI and 2 with ILC) and autosomal syndromic ichthyosis (1 patient) were screened by a custom Agilent HaloPlex multi-gene panel and the segregation of causative mutations were analyzed in available family members. Results Clinical and molecular characterization, leading to genotype–phenotype correlation in 11 Tunisian patients was carried out. Overall, we identified 8 mutations in 5 genes. Thus, in patients with ARCI, we i...

JDDG: Journal der Deutschen Dermatologischen Gesellschaft, 2021

Acta Dermato Venereologica, 2020

Fig. 1. (a-c) Representative lesions of sebaceous naevus and papular naevi spili in a 41-year-old... more Fig. 1. (a-c) Representative lesions of sebaceous naevus and papular naevi spili in a 41-year-old patient with phacomatosis pigmentokeratotica. (d) Squamous cell carcinoma in the naevus sebaceous on the scalp with regional nodal metastasis.

Annales de Dermatologie et de Vénéréologie, 2019

Journal of Investigative Dermatology, 2019

Brooke-Spiegler syndrome (BSS; OMIM 605041) is a rare monogenic skin disease characterized by the... more Brooke-Spiegler syndrome (BSS; OMIM 605041) is a rare monogenic skin disease characterized by the development of skin appendage tumors caused by mutations in the cylindromatosis gene (CYLD). Concerning the so far reported phenotypes and the underlying CYLD mutations, it is difficult to establish genotype-phenotype correlations in BSS. We have recently investigated a Hungarian family (with Bukovinian origin) and an Anglo-Saxon BSS pedigree, in whom the affected family members-despite of carrying the same diseasecausing mutation (c.2806C>T, p.Arg936X) of the CYLD gene-show striking differences in their phenotypes. The aim of our study was to identify phenotype modifier genetic factors, which could help the understanding of genotype-phenotype correlations in BSS. Comparing the WES data of the Hungarian and Anglo-Saxon BSS patients, here we have identified three putative phenotype modifying genetic variants: the rs1053023 SNP of the signal transducer and activator of transcription 3 (STAT3) gene, the rs1131877 SNP of the tumor necrosis factor receptor-associated factor 3 (TRAF3) gene and the rs202122812 SNP of the neighbor of BRCA1 gene 1 (NBR1) gene. Our study contributes to the accumulating evidence describing the clinical importance of genetic phenotype modifying factors, which have high potential in the elucidation of genotype-phenotype correlations and disease prognosis.

Frontiers in Neurology, 2019

Chorea-acanthocytosis (ChAc) is a rare, adult-onset disease usually characterized by, hence the n... more Chorea-acanthocytosis (ChAc) is a rare, adult-onset disease usually characterized by, hence the name, a movement disorder and acanthocytosis in the blood. It is caused by mutations of the VPS13A gene with an autosomal recessive transmission. We report a consanguineous Turkish family with a different and informative clinical and diagnostic course. Three siblings developed seizures and the index patient had been diagnosed with bilateral temporal lobe epilepsy. A key finding, however, was the basal ganglia involvement in neuroimaging although no movement disorder was present. [ 18 F]FDG-PET showed a prominent decline in striatal glucose metabolism at 31 years of age and [ 123 I]FP-CIT-SPECT revealed a moderate loss of striatal dopamine transporter availability. The family was referred for genetic testing and exome sequencing detected a homozygous novel truncating mutation c.4326 T>A (p.Tyr1442 *) in VPS13A in all affected siblings. With this case, we present autosomal recessive epilepsy as the predominant phenotype of ChAc with a new homozygous VPS13A mutation and provide pathological structural and molecular neuroimaging findings.

British Journal of Dermatology, 2018

Go to publication entry in University of Southern Denmark's Research Portal Terms of use This wor... more Go to publication entry in University of Southern Denmark's Research Portal Terms of use This work is brought to you by the University of Southern Denmark. Unless otherwise specified it has been shared according to the terms for self-archiving. If no other license is stated, these terms apply: • You may download this work for personal use only. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying this open access version If you believe that this document breaches copyright please contact us providing details and we will investigate your claim.

Journal of Biological Chemistry, 2008

Adipose triglyceride lipase (ATGL) catalyzes the first step in the hydrolysis of triacylglycerol ... more Adipose triglyceride lipase (ATGL) catalyzes the first step in the hydrolysis of triacylglycerol (TG) generating diacylglycerol and free fatty acids. The enzyme requires the activator protein CGI-58 (or ABHD5) for full enzymatic activity. Defective ATGL function causes a recessively inherited disorder named neutral lipid storage disease that is characterized by systemic TG accumulation and myopathy. In this study, we investigated the functional defects associated with mutations in the ATGL gene that cause neutral lipid storage disease. We show that these mutations lead to the expression of either inactive enzymes localizing to lipid droplets (LDs) or enzymatically active lipases with defective LD binding. Additionally, our studies assign important regulatory functions to the C-terminal part of ATGL. Truncated mutant ATGL variants lacking ϳ220 amino acids of the C-terminal protein region do not localize to LDs. Interestingly, however, these mutants exhibit substantially increased TG hydrolase activity in vitro (up to 20-fold) compared with the wild-type enzyme, indicating that the C-terminal region suppresses enzyme activity. Protein-protein interaction studies revealed an increased binding of truncated ATGL to CGI-58, suggesting that the C-terminal part interferes with CGI-58 interaction and enzyme activation. Compared with the human enzyme, the C-terminal region of mouse ATGL is much less effective in suppressing enzyme activity, implicating species-dependent differences in enzyme regulation. Together, our results demonstrate that the C-terminal region of ATGL is essential for proper localization of the enzyme and suppresses enzyme activity. Adipose triglyceride lipase (ATGL; official gene symbol: PNPLA2, patatin-like phospholipase domain containing 2) 3 is * This work was supported by Grant P18434-B05 from the Austrian Fonds zur Fö rderung der wissenschaftlichen Forschung and "GOLD-Genomics of Lipid-Associated Disorders," which is part of the Austrian Genome Project "GEN-AU Genome Research in Austria" and is funded by the Austrian Ministry for Education, Research, and Culture.

Acta Dermato Venereologica, 2020

This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Acta Derm ... more This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Acta Derm Venereol 2020; 100: adv00096 Centenary theme section: GENODERMATOSES SIGNIFICANCE Knowledge of the molecular genetic causes and mechanisms of hereditary ichthyoses has increased hugely since the 1990s due to the ubiquitous application of modern sequencing technologies. It is important for doctors and scientists that this new knowledge is clinically and genetically correctly classified, in order to make diagnosis and differential diagnosis easier. This article provides an overview of the genetic background and clinical features of ichthyoses and related cornification disorders. Inherited ichthyoses are classified as Mendelian disorders of cornification (MEDOC), which are defined on the basis of clinical and genetic features and are mainly divided into non-syndromic and syndromic ichthyoses. Numerous genes, which encode for corresponding proteins, are involved in the normal differentiation of keratinocytes (cornification) and participate in the formation of a functional epidermal barrier. To date, mutations in more than 50 genes are known to result in various types of ichthyoses. Thanks to modern genetic diagnostic methods based on targeted next generation sequencing (NGS), approximately 80-90% of cases can be resolved at present. Further sequencing methods covering the whole exome (WES) or whole genome (WGS) will obviously elucidate another portion of the remaining unknown ichthyoses in the future.

Genes

Autosomal recessive congenital ichthyosis (ARCI) is a non-syndromic congenital disorder of cornif... more Autosomal recessive congenital ichthyosis (ARCI) is a non-syndromic congenital disorder of cornification characterized by abnormal scaling of the skin. The three major phenotypes are lamellar ichthyosis, congenital ichthyosiform erythroderma, and harlequin ichthyosis. ARCI is caused by biallelic mutations in ABCA12, ALOX12B, ALOXE3, CERS3, CYP4F22, NIPAL4, PNPLA1, SDR9C7, SULT2B1, and TGM1. The most severe form of ARCI, harlequin ichthyosis, is caused by mutations in ABCA12. Mutations in this gene can also lead to congenital ichthyosiform erythroderma or lamellar ichthyosis. We present a large cohort of 64 patients affected with ARCI carrying biallelic mutations in ABCA12. Our study comprises 34 novel mutations in ABCA12, expanding the mutational spectrum of ABCA12-associated ARCI up to 217 mutations. Within these we found the possible mutational hotspots c.4541G>A, p.(Arg1514His) and c.4139A>G, p.(Asn1380Ser). A correlation of the phenotype with the effect of the genetic muta...

British Journal of Dermatology

medizinische genetik, 2019

ZusammenfassungEpidermolysis bullosa hereditaria (EB) umfasst eine Gruppe von Erkrankungen, die m... more ZusammenfassungEpidermolysis bullosa hereditaria (EB) umfasst eine Gruppe von Erkrankungen, die mit Hautfragilität und mechanisch verursachter Blasenbildung einhergehen. Die klinischen Manifestationen zeigen unterschiedliche Schweregrade, von lebensbedrohlich bis leicht. Im Kindesalter und bei Erwachsenen kann das klinische Bild typisch sein; allerdings kann bei Neugeborenen der EB-Subtyp klinisch häufig nicht bestimmt werden. Pathogene Varianten in 20 Genen sind bereits als krankheitsursächlich für die verschiedenen Formen der EB beschrieben. Die allelische Heterogenität ist sehr groß. Die Diagnostik basiert auf der genauen klinischen Untersuchung, der Familienanamnese und der molekulargenetischen Analyse. Aufgrund der genetischen Heterogenität und der Größe der Gene eignet sich die „Next-generation-sequencing“-basierte Multi-Gen-Panel-Diagnostik am besten. Teilweise sind Genotyp-Phänotyp-Korrelationen bekannt, sodass die genetische Diagnostik auch prognostisch eine Rolle spielt.

American Journal of Medical Genetics Part A, 2005

British Journal of Dermatology

Background Hyperkeratosis lenticularis perstans (HLP), also known as Flegel disease, is a rare sk... more Background Hyperkeratosis lenticularis perstans (HLP), also known as Flegel disease, is a rare skin disease presenting with asymptomatic small hyperkeratotic papules. The lesions often appear on the dorsal feet and lower legs, and typically develop after the fourth decade of life. A genetic basis for HLP is suspected; however, so far no gene defect linked to the development of HLP has been identified. Objectives We aimed to identify the genetic cause of HLP. Methods For mutational analysis we studied a cohort of five patients with HLP using next-generation sequencing (NGS). We used DNA ­extracted from fresh skin biopsies alongside ethylenediamine tetraacetic acid (EDTA) blood samples from two patients, and formalin-fixed ­paraffin-embedded skin biopsy material from three patients. In addition, immunofluorescence staining of HLP lesions from four patients was investigated. Results In all samples from the five patients with HLP we identified by NGS rare variants in the SPTLC1 gene. In...