A splicing mutation of the HMGA2 gene is associated with Silver-Russell syndrome phenotype (original) (raw)

12q14.3 microdeletion involving HMGA2 gene cause a Silver-Russell syndrome-like phenotype: a case report and review of the literature

Italian Journal of Pediatrics, 2020

Background Silver-Russell Syndrome (SRS) is a genetic disorder characterized by intrauterine and postnatal growth restriction and normal head circumference with consequent relative macrocephaly. Addictional findings are protruding forehead in early life, body asymmetry (of upper and lower limbs) and substantial feeding difficulties. Although several genetic mechanisms that cause the syndrome are known, more than 40% of patients with a SRS-like phenotype remain without an etiological diagnosis. In the last few years, different clinical reports have suggested that mutations or deletions of the HMGA2 gene can be responsible for a SRS-like phenotype in patients with negative results of the common diagnostic tests for this syndrome. Case presentation We present a 3-year-old male patient with clinical diagnosis of Silver-Russell Syndrome (SRS) associated with a de novo heterozygous deletion of the long arm of the chromosome 12 (12q14.3) encompassing the HMGA2 gene. Conclusions Our report ...

HMGA2 Variants in Silver-Russell Syndrome: Homozygous and Heterozygous Occurrence

The Journal of Clinical Endocrinology & Metabolism, 2020

Context Silver-Russell syndrome (SRS) is a clinical and molecular heterogeneous disorder associated with short stature, typical facial gestalt, and body asymmetry. Though molecular causes of SRS can be identified in a significant number of patients, about one-half of patients currently remain without a molecular diagnosis. However, determination of the molecular cause is required for a targeted treatment and genetic counselling. Objective The aim of this study was to corroborate the role of HMGA2 as an SRS-causing gene and reevaluate its mode of inheritance. Design, Setting, Patients Patients were part of an ongoing study aiming on SRS-causing genes. They were classified according to the Netchine-Harbison clinical scoring system, and DNA samples were investigated by whole exome sequencing. Common molecular causes of SRS were excluded before. Results Three novel pathogenic HMGA2 variants were identified in 5 patients from 3 SRS families, and fulfilling diagnostic criteria of SRS. For...

Structural and sequence variants in patients with Silver-Russell syndrome or similar features-Curation of a disease database

Human mutation, 2018

Silver-Russell syndrome (SRS) is a clinically and molecularly heterogeneous disorder involving prenatal and postnatal growth retardation, and the term SRS-like is broadly used to describe individuals with clinical features resembling SRS. The main molecular subgroups are loss of methylation of the distal imprinting control region (H19/IGF2:IG-DMR) on 11p15.5 (50%) and maternal uniparental disomy of chromosome 7 (5%-10%). Through a comprehensive literature search, we identified 91 patients/families with various structural and small sequence variants, which were suggested as additional molecular defects leading to SRS/SRS-like phenotypes. However, the molecular and phenotypic data of these patients were not standardized and therefore not comparable, rendering difficulties in phenotype-genotype comparisons. To overcome this challenge, we curated a disease database including (epi)genetic phenotypic data of these patients. The clinical features are scored according to the Netchine-Harbis...

The genetic aetiology of Silver-Russell syndrome

Journal of Medical Genetics, 2007

Silver-Russell syndrome (SRS MIM180860) is a disorder characterised by intrauterine and/or postnatal growth restriction and typical facies. However, the clinical picture is extremely diverse due to numerous diagnostic features reflecting a heterogeneous genetic disorder. The mode of inheritance is variable with sporadic cases also being described. Maternal uniparental disomy (mUPD) of chromosome 7 accounts for 10% of SRS cases and many candidate imprinted genes on 7 have been investigated. Chromosome 11 has moved to the forefront as the key chromosome in the aetiology, with reports of methylation defects in the H19 imprinted domain associated with the phenotype in 35-65% of SRS patients. Methylation aberrations have been described in a number of other imprinted growth related disorders such as Beckwith-Wiedmann syndrome. This review discusses these recent developments as well as the previous work on chromosome 7. Other candidate genes/chromosomal regions previously investigated are tabled.

Silver-Russell Syndrome – Part I: Clinical Characteristics and Genetic Background

Pediatric Endocrinology Diabetes and Metabolism, 2014

Silver-Russell syndrome (SRS) is a rare, clinically and genetically heterogeneous entity, caused by (epi)genetic alternations. It is characterized by prenatal and postnatal growth retardation, relative macrocephaly, the triangular face and body asymmetry. About 40-60% of cases are caused by hypomethylation of 11p.15.5 Imprinting Centre Region 1 (ICR1) on the paternal chromosome, and maternal uniparental disomy for chromosome 7 (UPD(7)mat) is found in 5-10% of cases. There are suggested correlations between genotype and the phenotype. Psychomotor development may be delayed, usually mildly, with school difficulties and speech delay more common in patients with UPD(7)mat. Children with 11p15 hypomethylation are shorter and lighter at birth in comparison to children with UPD(7)mat, however further deceleration tends to be more apparent in the latter group. The onset of puberty tends to occur early, with acceleration of bone age, resulting in less apparent growth spurt. Failure to thrive and feeding problems are characteristic for the infant period, and further development of a child may be conditioned by additional congenital defects.

Silver-Russell syndrome: a dissection of the genetic aetiology and candidate chromosomal regions

Journal of Medical Genetics, 2001

The main features of Silver-Russell syndrome (SRS) are pre-and postnatal growth restriction and a characteristic small, triangular face. SRS is also accompanied by other dysmorphic features including fifth finger clinodactyly and skeletal asymmetry. The disorder is clinically and genetically heterogeneous, and various modes of inheritance and abnormalities involving chromosomes 7, 8, 15, 17, and 18 have been associated with SRS and SRS-like cases. However, only chromosomes 7 and 17 have been consistently implicated in patients with a strict clinical diagnosis of SRS. Two cases of balanced translocations with breakpoints in 17q23.3-q25 and two cases with a hemizygous deletion of the chorionic somatomammatropin gene (CSH1) on 17q24.1 have been associated with SRS, strongly implicating this region. Maternal uniparental disomy for chromosome 7 (mUPD(7)) occurs in up to 10% of SRS patients, with disruption of genomic imprinting underlying the disease status in these cases. Recently, two SRS patients with a maternal duplication of 7p11.2-p13, and a single proband with segmental mUPD for the region 7q31-qter, were described. These key patients define two separate candidate regions for SRS on both the p and q arms of chromosome 7. Both the 7p11.2-p13 and 7q31-qter regions are subject to genomic imprinting and the homologous regions in the mouse are associated with imprinted growth phenotypes. This review provides an overview of the genetics of SRS, and focuses on the newly defined candidate regions on chromosome 7. The analyses of imprinted candidate genes within 7p11.2-p13 and 7q31-qter, and gene candidates on distal 17q, are discussed.

Molecular Genetic Studies of Human Chromosome 7 in Russell–Silver Syndrome

Genomics, 2002

Russell-Silver syndrome (RSS; MIM 180860) is characterized by congenital short stature, relative macrocephaly with a triangular facies and downturned mouth, body asymmetry, and fifth-finger clinodactyly [1,2]. The genetic etiology of the syndrome is unknown and seems to be heterogeneous. Familial occurrence [3-5] and occasional chromosomal abnormalities [6-11] were described, indicating a genetic cause of the syndrome. Chromosome 7 has been considered to be involved in the etiology of RSS because 7% of sporadic patients demonstrate maternal uniparental disomy for chromosome 7 (mUPD7) [12-14], whereas normal growth and development were observed in patients with paternal UPD7 [15]. Considering these facts, the RSS phenotype in patients with mUPD7 has been considered to be due to an abnormality in an imprinted gene or region on chromosome 7, rather than homozygosity for a mutant recessive allele. One RSS patient with segmental mUPD7 (7q31-qter) was identified recently [16]. Paternal isodisomy of 7p and maternal isodisomy of 7q

The spectrum of Silver-Russell syndrome: a clinical and molecular genetic study and new diagnostic criteria

Journal of medical genetics, 1999

The Silver-Russell syndrome (SRS) is characterised by severe intrauterine growth retardation, with a preserved head circumference, leading to a lean body habitus and short stature. Facial dysmorphism and asymmetry are considered typical features of the syndrome, although the range of phenotypic variance is unknown. Fifty seven subjects varying in age from 0.84 to 35.01 years, in whom the diagnosis of SRS had been considered definite or likely, were re-evaluated in a combined clinical and molecular study by a single observer (SMP). In 50 patients the clinical findings complied with a very broad definition of SRS. Notable additional findings included generalised camptodactyly seen in 11 (22%), many with distal arthrogryposis. Thirteen of the 25 males required genital surgery for conditions including hypospadias and inguinal hernia. Fourteen (36.8%) subjects above school age have received a statement of special educational needs. Molecular genetic analysis was performed in 42 subjects ...

Maternally derived 15q11.2-q13.1 duplication and H19-DMR hypomethylation in a patient with Silver-Russell syndrome

Journal of human genetics, 2017

Silver-Russell syndrome (SRS) is a congenital developmental disorder characterized by intrauterine and postnatal growth failure, craniofacial features (including a triangular shaped face and broad forehead), relative macrocephaly, protruding forehead, body asymmetry and feeding difficulties. Hypomethylation of the H19 differentially methylated region (DMR) on chromosome 11p15.5 is the most common cause of the SRS phenotype. We report the first SRS patient with hypomethylation of the H19-DMR and maternally derived 15q11.2-q13.1 duplication. Although her clinical manifestations overlapped with those of previously reported SRS cases, the patient's intellectual disability and facial dysmorphic features were inconsistent with the SRS phenotype. Methylation analyses, array comparative genomic hybridization, and a FISH analysis revealed the hypomethylation of the H19-DMR and a maternally derived interstitial 5.7 Mb duplication at 15q11.2-q13.1 encompassing the Prader-Willi/Angelman cri...

Atypical Silver-Russell phenotype resulting from maternal uniparental disomy of chromosome 7

American Journal of Medical Genetics Part A, 2010

We report on a patient with atypical Silver-Russell phenotype comprising severe growth retardation, unusual facies, bilateral Duane anomaly and infantile hypercalcemia caused by maternal uniparental iso/heterodisomy (mUPD) of chromosome 7. The development of myoclonus in this patient lends further support to the hypothesis that abnormal imprinting of the SGCE gene is responsible for some cases of myoclonus-dystonia syndrome. This case highlights the utility of SNP microarray technology as an accessible tool for the diagnosis of mUPD7 in atypical cases. We propose that depending on the balance of iso-and heterodisomic segments in a particular patient, mUPD7 may result in a range of phenotypes not confined to classic Silver-Russell syndrome. Ó