Evidence of Germline Mosaicism for a Novel BCOR Mutation in Two Indian Sisters with Oculo-Facio-Cardio-Dental Syndrome

In this study, we report on 2 sisters from India with oculo-facio-cardio-dental (OFCD) syndrome caused by a novel heterozygous mutation c.3490C>T (p.R1164*) in the BCOR gene. OFCD syndrome is an X-linked inherited disorder which is lethal in males. Interestingly, both parents of the sisters were phenotypically normal, and DNA analysis from blood and buccal or saliva cells failed to detect the BCOR mutation found in their 2 daughters. To the best of our knowledge, for the first time, we provide indirect evidence of germline mosaicism for the BCOR mutation in one of the parents of the 2 sisters affected by OFCD syndrome. Although this condition is lethal in males, gonadal mosaicism could also be present in the father. The relevance of clinical diagnosis and mutation analysis required for genetic counseling is described in this family.

Patient with mutation in the matrix metalloproteinase 2 (MMP2) gene - a case report and review of the literature

Torg and Winchester syndromes and patients reported by Al-AqeelSawairi as well as nodulosis-arthropathy-osteolysis (NAO) patients, patients with multicentric NAO share autosomal recessive inheritance. The common presenting symptomatology includes progressive osteolysis chiefly affecting the carpal, tarsal and interphalangeal joints. Here, we report a patient with Torg syndrome. Torg syndrome is caused by homozygous or compound heterozygous mutations in the matrix metalloproteinase 2 (MMP2) gene. MMP2 codes for a gelatinase that cleaves type IV collagen, a major component of basement membrane. The clinical presentation of our patient included moderate osteolysis of the small joints of the hands and knees, hirsutism, nodulosis sparing the palms and soles, corneal opacities and mild facial dysmorphism without gum hypertrophy. Genetic analysis showed that the patient was homozygous for a novel base variant c538 G>A (p.D180N) in the MMP2 gene. Both parents were carriers of the same mutated variant. Our patient had some previously unreported endocrine manifestations such as premature thelarche and elevated follicle-stimulating hormone levels.

Renal manifestations of tuberous sclerosis among children: an Indian experience and review of the literature

Objective

The objective of this study was to describe the renal manifestations in children 0–18 years of age diagnosed with tuberous sclerosis complex (TSC) at a tertiary hospital in South India.

Methods

Data of children with TSC, who presented to Christian Medical College Vellore Hospital from January 2008 to January 2013, were analysed by a retrospective chart review. The cases were identified from outpatient records and underwent ultrasonography, urine analysis and examination of serum creatinine to recognize renal involvement.

Results

Twenty-five children with TSC were identified. Two children did not have imaging studies available and were excluded from the analysis. The age of the included children ranged from 5 days to 15 years with a median age of 8 years. Seventy-four per cent (17/23) were males. Ten of the 23 children had evidence of renal involvement (43.5%). Of the 10 children with renal involvement, 6 had angiomyolipoma (60%), 5 had renal cysts (50%) and 1 had suspected renal cell carcinoma. In two children both angiomyolipoma (AML) and cysts were noted. One child was found to have proteinuria. The rest of the children had no evidence of proteinuria and had normal creatinine clearance.

Conclusion

We conclude that all children with TSC should be screened for renal involvement and regular follow-up should be arranged.

Clinical utility of multiplex ligation-dependent probe amplification technique in identification of aetiology of unexplained mental retardation: a study in 203 Indian patients

BACKGROUND & OBJECTIVES

Developmental delay (DD)/mental retardation also described as intellectual disability (ID), is seen in 1-3 per cent of general population. Diagnosis continues to be a challenge at clinical level. With the advancement of new molecular cytogenetic techniques such as cytogenetic microarray (CMA), multiplex ligation-dependent probe amplification (MLPA) techniques, many microdeletion/microduplication syndromes with DD/ID are now delineated. MLPA technique can probe 40-50 genomic regions in a single reaction and is being used for evaluation of cases with DD/ID. In this study we evaluated the clinical utility of MLPA techniques with different probe sets to identify the aetiology of unexplained mental retardation in patients with ID/DD.

METHODS

A total of 203 randomly selected DD/ID cases with/without malformations were studied. MLPA probe sets for subtelomeric regions (P070/P036) and common microdeletions/microduplications (P245-A2) and X-chromosome (P106) were used. Positive cases with MLPA technique were confirmed using either fluorescence in situ hybridization (FISH) or follow up confirmatory MLPA probe sets.

RESULTS

The overall detection rate was found to be 9.3 per cent (19 out of 203). The detection rates were 6.9 and 7.4 per cent for common microdeletion/microduplication and subtelomeric probe sets, respectively. No abnormality was detected with probe set for X-linked ID. The subtelomeric abnormalities detected included deletions of 1p36.33, 4p, 5p, 9p, 9q, 13q telomeric regions and duplication of 9pter. The deletions/duplications detected in non telomeric regions include regions for Prader Willi/Angelman regions, Williams syndrome, Smith Magenis syndrome and Velocardiofacial syndrome.

INTERPRETATION & CONCLUSIONS

Our results show that the use of P245-A2 and P070/P036-E1 probes gives good diagnostic yield. Though MLPA cannot probe the whole genome like cytogenetic microarray, due to its ease and relative low cost it is an important technique for evaluation of cases with DD/ID.

Juvenile ankylosing spondylitis in Turner syndrome

Juvenile ankylosing spondylitis (JAS) is a chronic autoimmune disorder which causes considerable morbidity when left untreated; it occurs predominantly in men. We describe an Asian Indian woman who had JAS with phenotypic features of Turner syndrome (TS) and was found to be a mosaic for 45, X/46, X, psu idic (X) (p11) by karyotyping and fluorescence in situ hybridization (FISH) studies of peripheral blood. The absence of Y chromosome material was confirmed by FISH. Haplo-insufficiency of the X chromosome can predispose to autoimmunity. To the best of our knowledge, this is the first report of JAS in association with mosaic Turner syndrome. This case highlights the possible effects of gene dosage in development of an autoimmune disease.

Tumour necrosis factor (TNF)-α-308 gene polymorphism in Indian patients with Takayasu's arteritis - a pilot study

BACKGROUND & OBJECTIVES

Tumour necrosis factor-alpha (TNF-α)- 308 promoter gene polymorphism has been shown to be associated with several autoimmune disorders and infections such as tuberculosis. There is no study on TNF-α gene polymorphism in Takayasu's arteritis (TA) till date. We aimed to study this polymorphism in TA, a granulomatous vasculitis, probably triggered by Mycobacterium tuberculosis.

METHODS

TNF-α - 308 gene polymorphism was studied in 34 patients with TA and 39 healthy controls recruited from Christian Medical College, India. PCR was done followed by enzyme digestion. G and A polymorphisms were analysed. Occurrence of alleles in the disease group was compared with controls as well as with historical controls.

RESULTS

GG allele was most frequent in TA and in controls. GA allele was detected in four controls but only in one patient who was the oldest in the study group. AA polymorphism was detected in one control but not in TA. When compared with controls from other populations, it was found that our allelic frequency was similar to that in Japan as well as from USA with mixed population. However, predominantly Caucasian population studied from Netherlands, Germany and England, where TA is rare, had a higher frequency of A allele as compared to our controls.

INTERPRETATION & CONCLUSIONS

Our preliminary results indicated that G allele at TNF-α - 308 was more common in TA patients and controls similar to that in other Indian as well as Japanese population. Compared to the western population, A allele was relatively less common in our study subjects.

Cri du chat syndrome: a series of five cases

The cri du chat syndrome (CdCS) is a chromosomal deletion syndrome associated with a partial deletion of the short (p) arm of chromosome 5. We describe five children who were diagnosed to have CdCS by conventional cytogenetic analysis. The deletion was at 5p15 in four patients, whereas the fifth had a larger, more proximal deletion at 5p14. Fluorescence in situ hybridization (FISH) analysis confirmed the deletion of the CdCS critical region at 5p15.2. All five children had global developmental delay and dysmorphism with microcephaly. The other clinical features were variable. Since the clinical diagnosis of CdCS may not always be evident because of the phenotypic heterogeneity, cytogenetic analysis is necessary to establish the diagnosis and confirm that the deletion involves the CdCS critical region. This will enable early intervention which plays an important role in improving the outcome.

Tel Hashomer camptodactyly syndrome: a case report

Tel Hashomer camptodactyly syndrome (THCS) is a rare autosomal recessive camptodactyly with muscular involvement. The manifestations of THCS other than camptodactyly are clubbed feet, thenar and hypothenar hypoplasia, abnormal palmar creases and dermatoglyphic ridges, spina bifida and mitral valve prolapse. The syndrome was first described by Goodman et al in 1972 and thereafter two further cases with similar phenotype were seen. Herein, we present another case report and review of the literature of other syndromes associated with camptodactyly and mitral valve prolapse. Further cases with this syndrome need to be reported for mapping of the candidate loci. This will help in planning management and genetic counselling.

An Indian boy with additional features in Pallister-Killian syndrome

Pallister-Killian syndrome (PKS; OMIM: # 601803) is a rare sporadic genetic disorder characterized by pigmentary skin changes, distinctive dysmorphology, developmental delay, and mosaicism for tetrasomy of chromosome 12p. The authors report a case of PKS in a 2-y-old boy. He had pigmentary skin changes, characteristic facial features, developmental delay and hearing loss. He had sacral and post-auricular pits in addition, which has not yet been reported. A diagnosis of PKS was suspected on the basis of the patient's clinical features. Skin fibroblast culture was done which showed mosaic tetrasomy of isochromosome 12p consistent with Pallister-Killian syndrome. This case highlights the importance of dysmorphology as a diagnostic tool for recognition and accurate genetic counseling in genetic syndromes.

A case report of fibular aplasia, tibial campomelia, and oligosyndactyly (FATCO) syndrome associated with Klinefelter syndrome and review of the literature

Limb development is a complex regulated development phenomenon involving multiple genes. Fibular Aplasia, Tibial Campomelia and Oligosyndactyly (FATCO) syndrome (MIM#246570) is a syndrome of unknown genetic basis and inheritance with variable expressivity and penetrance. Its counterpart, Fuhrmann syndrome or Femoral-Fibularaplasia-Campomelia and Oligosyndactyly are a result of defect in the WNT7a gene located on the 3p25. Former is proposed to be a development dysplasia of defective dorso-ventral polarity assignment and distal limb development. Ectrodactyly and fibular a/hypoplasia (EFA, MIM# 113310) share the full phenotypic spectrum of FATCO syndrome, whether they are allelic disorders or represent two variable presentations in the spectrum of the same disorder is not an established fact. We report here one Indian patient with findings of FATCO syndrome with associated Klinefelter syndrome. This is the first such report which is likely to be a co-incidental finding and has implications for genetic counseling.

LEVELS OF EVIDENCE

Therapeutic, Level IV.

ATR-X syndrome in two siblings with a novel mutation (c.6718C>T mutation in exon 31)

ATR-X syndrome is an X-linked mental retardation syndrome characterized by mental retardation, alpha thalassaemia and distinct facial features which include microcephaly, frontal hair upsweep, epicanthic folds, small triangular nose, midface hypoplasia and carp-shaped mouth. Here we report two brothers with clinical features of ATR-X syndrome, in whom a novel missense (C>T) mutation was identified in exon 31 of the ATRX gene.

Development and dysmorphism in Joubert syndrome--short case series from India

Five children with Joubert syndrome (JS), who fulfilled the criteria and had molar tooth sign (MTS) on magnetic resonance imaging were included in the study. Prominent forehead, open mouth and low set ears were consistent facial features. Severe developmental delay was seen in three children (66%). A differential developmental delay was noticed in all children and was independent of the radiological features. The children who had complications in the neonatal period were found to have more developmental delay on follow-up. The optimal control of sleep disturbances and hyperkinesis in one child resulted in a better cognitive performance. A regular neuro-developmental follow-up and interventions can optimize the potential of children with JS. In addition to the regular screening for retinal, renal and hepatic functions in JS, there is a need to monitor cognitive functions, sleep and behavior.

Klinefelter syndrome with systemic lupus erythematosus in an Indian man

Previously, cases of systemic lupus erythematosus (SLE) and Klinefelter syndrome (KS) in men have been reported in Western populations. We report the case of a 30-year-old man from southern India with known infertility who was diagnosed to have SLE and KS by fluorescence in-situ hybridization, as routine karyotype cultures failed. The diagnosis has implications in management and highlights the need for strong clinical suspicion and laboratory confirmation of KS by molecular methods when suspected in all men with SLE. Quicker, long-term remission and genetic counseling of such individuals can help in better management and coping with this chronic, potentially fatal disease. Lupus (2010) 19, 870-871.

An Indian boy with nephropathic cystinosis: a case report and molecular analysis of CTNS mutation

Cystinosis is a rare autosomal recessive lysosomal storage disorder characterized by excessive accumulation of cystine within the lysosome. Cystinosis is caused by mutations in the lysosomal cystine transporter, cystinosin (CTNS). The CTNS gene consists of 12 exons and encodes for an integral lysosomal membrane protein with seven transmembrane domains. A majority of cystinotic patients are of European descents, and only a few cases have been reported from other ethnic groups. Here we report a case of nephropathic cystinosis in an Indian boy born to consanguineous parents. Major symptoms of the patient include weight loss, vomiting, dehydration, and cystine crystals in the cornea. Ichthyosis on the arms and legs is also observed. Sequencing analysis of all the CTNS exons revealed that the proband is homozygous for a 3-bp in-frame deletion in exon 10 (c.809_811delCCT), resulting in the loss of a conserved p.Ser270del within the fifth transmembrane domain of CTNS. His parents are both heterozygous for the same mutation. This work represents the first molecular characterization of cystinotic patients from India. Interestingly, a p.Ser270del resulting from c.809_811delCCT in CTNS had been identified in a European patient. Therefore, it appears that this mutation arose independently in the two different continents.

Mutations in C2orf37, encoding a nucleolar protein, cause hypogonadism, alopecia, diabetes mellitus, mental retardation, and extrapyramidal syndrome

Hypogonadism, alopecia, diabetes mellitus, mental retardation, and extrapyramidal syndrome (also referenced as Woodhouse-Sakati syndrome) is a rare autosomal recessive multisystemic disorder. We have identified a founder mutation consisting of a single base-pair deletion in C2orf37 in eight families of Saudi origin. Three other loss-of-function mutations were subsequently discovered in patients of different ethnicities. The gene encodes a nucleolar protein of unknown function, and the cellular phenotype observed in patient lymphoblasts implicates a role for the nucleolus in the pathogenesis of this disease. Our findings expand the list of human disorders linked to the nucleolus and further highlight the developmental and/or maintenance functions of this organelle.

Premature ovarian failure in a patient with a complex chromosome rearrangement involving the critical region Xq24, characterized by analysis using fluorescence in situ hybridization by chromosome microdissection

OBJECTIVE

To characterize a complex chromosome rearrangement previously detected by G-banding in peripheral blood lymphocytes as 46,X, inv(X)(p11;q2?), inv(4)(q?),ins(8)(q?) in a patient with primary amenorrhea.

DESIGN

Case report.

SETTING

University faculty of medicine and hospital.

PATIENT(S)

A 16-year-old girl with primary amenorrhea.

INTERVENTION(S)

Microdissection of chromosomes labeled by fluorescence in situ hybridization and by reverse painting.

MAIN OUTCOME MEASURE(S)

Use of commercial whole-chromosome painting probes for the detection of the aberrant chromosomes 4, 8, and X. Fluorescence probes of the isolated derivative chromosomes are self-generated.

RESULT(S)

The use of whole-chromosome painting probes allowed reliable identification of all chromosomes involved in the complex chromosome rearrangements. The DNA of those chromosomes was amplified and fluorescence labeled by polymerase chain reaction using degenerated oligonucleotide primers. These probes revealed breakpoints of the complex chromosome rearrangement by hybridization on normal and original chromosomes in 4q31.1, 8q24.1, Xp22.1, Xp11.4, and Xq24.

CONCLUSION(S)

We report on an Indian patient who has premature ovarian failure with primary amenorrhea as well as a hormone level increased for LH and FSH but decreased for TSH. She has a balanced complex translocation with three breakpoints in the X chromosome that were located by fluorescence in situ hybridization by chromosome microdissection, but no breakpoints localized in the critical regions for premature ovarian failure on the X chromosome. The breakpoint in Xq24 may be associated with the amenorrhea.

Mutations of the AAAS gene in an Indian family with Allgrove's syndrome

The triple A or Allgrove's syndrome is an autosomal recessive disorder characterized by the triad of achalasia cardia, alacrima and ACTH resistant adrenocortical insufficiency. Mutations of the Achalasia-Addisonianism-Alacrima-Syndrome (AAAS) gene on chromosome 12q13 are associated with this syndrome. We report an Indian family where two siblings were homozygous for a known mutation of the AAAS gene and presented with the classical triad of symptoms. The mother and the brother were heterozygous and asymptomatic. The affected siblings had iron deficiency anemia and the younger sister had pes cavus and palmoplantar keratosis. Neurological symptoms were absent in both affected children. Recognition of this syndrome can lead to early treatment of adrenal insufficency and genetic counselling.

Four common glomulin mutations cause two thirds of glomuvenous malformations ("familial glomangiomas"): evidence for a founder effect

BACKGROUND

Glomuvenous malformation (GVM) ("familial glomangioma") is a localised cutaneous vascular lesion histologically characterised by abnormal smooth muscle-like "glomus cells" in the walls of distended endothelium lined channels. Inheritable GVM has been linked to chromosome 1p21-22 and is caused by truncating mutations in glomulin. A double hit mutation was identified in one lesion. This finding suggests that GVM results from complete localised loss of function and explains the paradominant mode of inheritance.

OBJECTIVE

To report on the identification of a mutation in glomulin in 23 additional families with GVM.

RESULTS

Three mutations are new; the others have been described previously. Among the 17 different inherited mutations in glomulin known up to now in 43 families, the 157delAAGAA mutation is the most common and was present in 21 families (48.8%). Mutation 108C-->A was found in five families (11.8%), and the mutations 554delA+556delCCT and 1179delCAA were present together in two families (4.7% each). Polymorphic markers suggested a founder effect for all four mutations.

CONCLUSIONS

Screening for these mutations should lead to a genetic diagnosis in about 70% of patients with inherited GVM. So far, a mutation in glomulin has been found in all GVM families tested, thus demonstrating locus homogeneity.

Genotype-phenotype correlation in Duchenne/Becker muscular dystrophy patients seen at Lucknow

The molecular basis of two allelic forms of muscular dystrophy, Duchenne (DMD) and Becker (BMD), has been explained by frame shift hypothesis. In order to test this hypothesis, deletional mutations in 59 patients confirmed to have DMD and 11 BMD patients were analysed using multiplex polymerase chain reaction and Southern hybridization with dystrophin cDNA probes. Translational reading frame of the dystrophin gene was derived from 'Border type' analysis of exons flanking the intragenic deletions. The correlation between genotype (reading frame) and phenotype (clinical severity) showed higher number of DMD patients (approximately 20%) deviating from the frame shift hypothesis. The patients who deviated had deletions at the central hot spot region of the dystrophin gene. The presence of these deviations in a large number of DMD patients highlights the difficulties in predicting the clinical progression of the disease based only on DNA profile.