Seven additional families with spondylocarpotarsal synostosis syndrome with novel biallelic deleterious variants in FLNB.

The location and/or type of variants in FLNB result in a spectrum of osteochondrodysplasias ranging from mild forms, like spondylocarpotarsal synostosis syndrome and Larsen syndrome, to severe perinatal lethal forms, such as atelosteogenesis I and III and Boomerang dysplasia. Spondylocarpotarsal synostosis syndrome is characterized by disproportionate short stature, vertebral anomalies and fusion of carpal and tarsal bones. Biallelic loss-of-function variants in FLNB are known to cause spondylocarpotarsal synostosis syndrome and 9 families and 9 pathogenic variants have been reported so far. We report clinical features of 10 additional patients from 7 families with spondylocarpotarsal synostosis syndrome due to 7 novel deleterious variants in FLNB, thus expanding the clinical and molecular repertoire of spondylocarpotarsal synostosis syndrome. Our report validates key clinical (fused thoracic vertebrae and carpal and tarsal coalition) and molecular (truncating variants in FLNB) characteristics of this condition.

Autosomal recessive IFT57 hypomorphic mutation cause ciliary transport defect in unclassified oral-facial-digital syndrome with short stature and brachymesophalangia.

The 13 subtypes of oral-facial-digital syndrome (OFDS) belong to the heterogeneous group of ciliopathies. Disease-causing genes encode for centrosomal proteins, components of the transition zone or proteins implicated in ciliary signaling. A unique consanguineous family presenting with an unclassified OFDS with skeletal dysplasia and brachymesophalangia was explored. Homozygosity mapping and exome sequencing led to the identification of a homozygous mutation in IFT57, which encodes a protein implicated in ciliary transport. The mutation caused splicing anomalies with reduced expression of the wild-type transcript and protein. Both anterograde ciliary transport and sonic hedgehog signaling were significantly decreased in subjects' fibroblasts compared with controls. Sanger sequencing of IFT57 in 13 OFDS subjects and 12 subjects with Ellis-Van Creveld syndrome was negative. This report identifies the implication of IFT57 in human pathology and highlights the first description of a ciliary transport defect in OFDS, extending the genetic heterogeneity of this subgroup of ciliopathies.

Identification and characterization of 20 novel pathogenic variants in 60 unrelated Indian patients with mucopolysaccharidoses type I and type II.

Mucopolysaccharidoses (MPS), a subgroup of lysosomal storage disorders, are caused due to deficiency of specific lysosomal enzyme involved in catabolism of glycosaminoglycans. To date more than 200 pathogenic variants in the alpha-l-iduronidase (IDUA) for MPS I and ∼500 pathogenic variants in the iduronate-2-sulphatase (IDS) for MPS II have been reported worldwide. The mutation spectrum of MPS type I and MPS type II disorders in Indian population is not characterized yet. In this study, we carried out clinical, biochemical, molecular and in silico analyses to establish the mutation spectrum of MPS I and MPS II in the Indian population. We conducted molecular analysis for 60 MPS-affected patients [MPS I (n = 30) (Hurler syndrome = 17, Hurler-Scheie syndrome = 13), and MPS II (n = 30) (severe = 18, attenuated = 12)] and identified a total of 44 [MPS I (n = 22) and MPS II (n = 22)] different pathogenic variants comprising missense, nonsense, frameshift, gross deletions and splice site variants. A total of 20 [MPS I (n = 14), and MPS II (n = 6)] novel pathogenic sequence variants were identified in our patient cohort. We found that 32% of pathogenic variants detected in IDUA were recurrent and 25% in MPS II. This is the first study revealing the mutation spectrum of MPS I and MPS II patients in the Indian population.

Utility and limitations of multiplex ligation-dependent probe amplification technique in the detection of cytogenetic abnormalities in products of conception.

Background and Introduction: Chromosomal abnormality is found in about half of first-trimester abortions. Karyotype is the gold standard to detect chromosomal abnormalities. Multiplex ligation-dependent probe amplification (MLPA) offers advantage over karyotype in terms of lower failure rate, faster turnaround time, and much higher resolution than conventional karyotyping and found to be 98% concordant with conventional karyotype. AIM: We performed this study to look for the utility of MLPA in diagnosing chromosomal abnormalities in first-trimester abortions. MATERIALS AND METHODS: MLPA using subtelomeric SALSA probe sets (P036 and P070) was used to detect cytogenetic abnormalities in products of conception in missed/spontaneous abortions. RESULTS: A total of ninety abortus samples were analyzed by MLPA. Successful results were provided in (67) 74.4% of the cases while no conclusion could be drawn in 25.6% (23) of the cases. Fifty-five (82.1%) cases were cytogenetically normal and 17.9% (12) had some abnormality. Aneuploidy was detected in 8 (66.7%) cases, 3 (25%) had double-segment imbalance, and one (8.3%) had partial aneuploidy. CONCLUSION: We suggest that MLPA is a good substitute to traditional karyotype.

Homozygous null mutations in ZMPSTE24 in restrictive dermopathy: evidence of genetic heterogeneity.

Restrictive dermopathy (RD) results in stillbirth or early neonatal death. RD is characterized by prematurity, intrauterine growth retardation, fixed facial expression, micrognathia, mouth in the 'o' position, rigid and tense skin with erosions and denudations and multiple joint contractures. Nearly all 25 previously reported neonates with RD had homozygous or compound heterozygous null mutations in the ZMPSTE24 gene. Here, we report three new cases of RD; all died within 3 weeks of birth. One of them had a previously reported homozygous c.1085dupT (p.Leu362PhefsX19) mutation, the second case had a novel homozygous c.1020G>A (p.Trp340X) null mutation in ZMPSTE24, but the third case, a stillborn with features of RD except for the presence of tapering rather than rounded, bulbous digits, harbored no disease-causing mutations in LMNA or ZMPSTE24. In the newborn with a novel ZMPSTE24 mutation, unique features included butterfly-shaped thoracic 5 vertebra and the bulbous appearance of the distal clavicles. Skin biopsies from both the stillborn fetus and the newborn with c.1020G>A ZMPSTE24 mutation showed absence of elastic fibers throughout the dermis. This report provides evidence of genetic heterogeneity among RD and concludes that there may be an additional locus for RD which remains to be identified.

A founder ectodysplasin A receptor (EDAR) mutation results in a high frequency of the autosomal recessive form of hypohidrotic ectodermal dysplasia in India.

BACKGROUND: Hypohidrotic/anhidrotic ectodermal dysplasia (HED) is a rare Mendelian disorder affecting ectodermal tissues. The disease is primarily caused by inactivation of any one of three genes, namely ectodysplasin A1 (EDA-A1), which encodes a ligand belonging to the tumour necrosis factor (TNF) superfamily; ectodysplasin A receptor (EDAR), encoding the EDA-A1 receptor and ectodysplasin A receptor-associated death domain (EDARADD), encoding an adaptor protein. X-linked recessive (EDA-A1), the predominant form of HED, as well as autosomal recessive and dominant (EDAR and EDARADD) inheritance patterns have been identified in affected families. OBJECTIVES: To determine the common genes causing HED in India. METHODS: We performed mutation analysis on 26 HED families from India (including 30 patients). In addition, we carried out sequence and structural analysis of missense/nonsense and insertion/deletion mutations. RESULTS: Among the 26 families analysed, disease-causing EDAR mutations were identified in 12 (46%) while EDA-A1 mutations were detected in 11 (42%). Four novel mutations in EDAR and five in EDA-A1 were identified. More importantly, a possible founder EDAR mutation, namely c.1144G>A, was identified in five independent families, thus accounting for about one-fifth of affected families in whom mutation was detected. A majority of EDA-A1 mutations localized to the TNF-like domain while the location of EDAR mutations was more widespread. CONCLUSIONS: This is the first report of a founder EDAR mutation and of a significantly high frequency of autosomal recessive HED.

Reciprocal balanced translocation: infertility and recurrent spontaneous abortions in a family.

In this case report we present a family with infertile, azoospermic but otherwise apparently healthy males with history of recurrent spontaneous abortions (RSA) in females. Karyotype of the infertile man revealed a reciprocal balanced translocation t(8; 13) with breakpoints at 8q22 and 13p11.2. The reported reciprocal balanced translocation is associated with azoospermia. The same translocation is probably the cause of RSA in females of the family.

Rhizomelic chondrodysplasia punctata type 1: report of mutations in 3 children from India.

Rhizomelic chondrodysplasia punctata is a rare autosomal recessive disorder characterized by stippled epiphyses and rhizomelic shortening of the long bones. We report 3 subjects of rhizomelic chondrodysplasia punctata from India and the PEX7 mutations identified in them. The common PEX7-L292X allele, whose high frequency is due to a founder effect in the northern European Caucasian population, was not identified in these patients. Instead, 2 novel alleles are described, including 64_65delGC, which was present on a single PEX7 haplotype and could represent a common allele in the Indian population.

Expanding CEP290 mutational spectrum in ciliopathies.

Ciliopathies are an expanding group of rare conditions characterized by multiorgan involvement, that are caused by mutations in genes encoding for proteins of the primary cilium or its apparatus. Among these genes, CEP290 bears an intriguing allelic spectrum, being commonly mutated in Joubert syndrome and related disorders (JSRD), Meckel syndrome (MKS), Senior-Loken syndrome and isolated Leber congenital amaurosis (LCA). Although these conditions are recessively inherited, in a subset of patients only one CEP290 mutation could be detected. To assess whether genomic rearrangements involving the CEP290 gene could represent a possible mutational mechanism in these cases, exon dosage analysis on genomic DNA was performed in two groups of CEP290 heterozygous patients, including five JSRD/MKS cases and four LCA, respectively. In one JSRD patient, we identified a large heterozygous deletion encompassing CEP290 C-terminus that resulted in marked reduction of mRNA expression. No copy number alterations were identified in the remaining probands. The present work expands the CEP290 genotypic spectrum to include multiexon deletions. Although this mechanism does not appear to be frequent, screening for genomic rearrangements should be considered in patients in whom a single CEP290 mutated allele was identified.

Uptake of invasive prenatal diagnostic tests in women after detection of soft markers for chromosomal abnormality on ultrasonographic evaluation.

OBJECTIVE: Use of soft ultrasonographic markers during routine prenatal ultrasonography (USG) may be used for the screening of aneuploidy in the low-risk population. The aim of this study was to evaluate the acceptance of an invasive test for prenatal diagnosis and to assess the role of various factors in the decision-making regarding an invasive test when confronted with risk for aneuploidy after a soft marker is detected on routine antenatal ultrasonogram. STUDY DESIGN: Women were referred for USG in our department by primary obstetricians for indications such as a previous child with a congenital malformation, genetic disorder, stillbirth or in women with recurrent spontaneous abortions. Some of the women were referred after prenatal detection of a soft marker on USG. They were screened for soft markers associated with chromosomal abnormality. They were counseled regarding the age-specific risk and the risk of aneuploidy after detection of a marker in comparison to the general population's risk of Down's syndrome. They were also counseled regarding the risk of a procedure-related abortion (0.5%) following an invasive procedure before their decision regarding the use of amniocentesis was made. RESULT: Twenty women out of 50 (40%) opted for amniocentesis. Except in one case of trisomy 21 in a fetus with short femur and humerus, all others had normal karyotype. The uptake of the test was comparable between primigravida (33%), women with poor obstetric history (46%) and women with at least one normal live child (45%). There was no statistical difference in the uptake of invasive test based on gestational age as well. Uptake of amniocentesis was higher (78%) in cases with nuchal thickening as compared to other markers (35%). CONCLUSION: Ultrasonographic detection of soft markers is associated with a high frequency of uptake for invasive prenatal testing. Increased nuchal thickening is associated with a higher acceptance of amniocentesis. Maternal age, gestational age or previous obstetric history were not associated with the decision to undergo amniocentesis.

Clinical utility of fetal autopsy and comparison with prenatal ultrasound findings.

OBJECTIVES: To present a comprehensive analysis of autopsy findings in 206 fetuses referred to our genetic center and to assess the clinical utility of fetal autopsy in reaching a final diagnosis, which is essential for counseling regarding the risk of recurrence. We also compared the autopsy findings with prenatal ultrasound findings to evaluate the potential benefit of fetal autopsy in fetuses terminated after prenatal diagnosis of malformations. STUDY DESIGN: Retrospective review of patient records in a tertiary referral genetic center in North India during 5-year period (April 2000-March 2005). This includes 206 fetuses, 138 terminated after detecting an anomaly in ultrasonogram and 68 spontaneous fetal losses. In all cases, fetal autopsy was carried out and complimented by radiography, karyotype wherever possible and histopathological examination wherever necessary. In fetuses with prenatally diagnosed malformations, ultrasound findings were compared with autopsy findings. RESULTS: Fetal autopsy was able to provide a definite final diagnosis in 59% (122/206) cases. Fetal autopsy confirmed the ultrasound findings in all cases but two. Moreover, autopsy provided additional findings in 77 cases and of these, 24 cases had a significant change of recurrence risk. CONCLUSION: This study confirms the utility of fetal autopsy in identifying the cause of fetal loss, which will help in the genetic counseling of the couple. In cases with prenatally diagnosed anomalies, the new information from fetal autopsy changes the predicted probability of recurrence in 18% cases. Even though the prenatal ultrasonogram reasonably predicts the malformations, fetal autopsy gives significant additional malformations in one-third of the cases and is essential for genetic counseling.

Quality of life and gender role behavior in disorders of sexual differentiation in India.

OBJECTIVE: Culture-specific tools to assess longterm psychosocial outcomes for patients with disorders of sexual differentiation are scant. We conducted a study to develop tools for evaluating gender role behavior and health related quality of life for Indian adolescent patients with intersex disorders. We also studied factors important to parents while deciding sex of rearing for their baby. METHODS: A 29-item gender role behavior questionnaire and an 18-item health related quality-of-life questionnaire were administered to 82 healthy controls, 13 patients with intersex disorders and 18 patients with type 1 diabetes mellitus. Internal consistency was checked by Cronbach's alpha and test-retest reliability using intra-class correlation coefficient. Responses of 28 parents to a questionnaire on factors affecting the decision of sex of rearing were recorded on a 5-point Likert scale in order of importance. RESULTS: Cronbach's alpha was 0.92 and 0.75, and intra-class correlation coefficient 0.76 and 0.75, for the gender role behavior and quality-of-life questionnaires respectively, indicating a high degree of internal consistency and stability. The mean composite scores for healthy girls on the gender role behavior questionnaire (82.5 +/- 8.7) differed significantly from that for healthy boys (53.2 +/- 7.1, p <0.001). Factors important to parents while making decisions for sex of rearing were appearance of the genitalia, medical advice, ability to bear children and economic independence. CONCLUSIONS: We have created valid tools to study gender role behavior and quality of life in adolescent patients with intersex disorders in India. We have also identified in a quantitative way the factors of greatest importance to parents while deciding sex of rearing. These results have direct utility in the management of patients with intersex disorders in India and other similar cultures.

A novel heterozygous missense mutation in uromodulin gene in an Indian family with familial juvenile hyperuricemic nephropathy.

Familial juvenile hyperuricemic nephropathy (FJHN), characterized by early-onset hyperuricemia, reduced fractional excretion of uric acid, and chronic renal failure is caused due to mutation in uromodulin (UMOD) gene. We identified a novel mutation in a family with multiple members affected with FJHN. Ten coding exons of UMOD gene in three family members with clinical and biochemical features of FJHN and one unaffected family member were sequenced, and sequence variants were analyzed for the pathogenicity by bioinformatics studies. A heterozygous novel missense mutation (c. 949 T >G) in exon 5 leading to the replacement of cysteine by glycine at position 317 was identified in all three affected family members. This mutation has not been reported earlier in Human Gene Mutation Database, Human Genome Variation, Clinvar, and 1000 Genome. The mutation lies in the cysteine-rich 2 domain of the protein, and the affected residue is evolutionary conserved in other species. To our knowledge, this is the first report of the identification of UMOD mutation in an Indian family.

Hypoxia stimulates osteopontin expression and proliferation of cultured vascular smooth muscle cells: potentiation by high glucose.

We examined the effect of hypoxia on proliferation and osteopontin (OPN) expression in cultured rat aortic vascular smooth muscle (VSM) cells. In addition, we determined whether hypoxia-induced increases in OPN and cell proliferation are altered under hyperglycemic conditions. Quiescent cultures of VSM cells were exposed to hypoxia (3% O(2)) or normoxia (18% O(2)) in a serum-free medium, and cell proliferation as well as the expression of OPN was assessed. Cells exposed to hypoxia for 24 h exhibited a significant increase in [(3)H]thymidine incorporation followed by a significant increase in cell number at 48 h in comparison with respective normoxic controls. Exposure to hypoxia produced significant increases in OPN protein and mRNA expression at 2 h followed by a gradual decline at 6 and 12 h, with subsequent significant increases at 24 h. Neutralizing antibodies to either OPN or its receptor beta3 integrin but not neutralizing antibodies to beta5 integrin prevented the hypoxia-induced increase in [(3)H]thymidine incorporation. Inhibitors of protein kinase C (PKC) and p38 mitogen-activated protein (MAP) kinase also reduced the hypoxia-induced stimulation of proliferation and OPN synthesis. Exposure to high-glucose (HG) (25 mmol/l) medium under normoxic conditions also resulted in significant increases in OPN protein and mRNA levels as well as the proliferation of VSM cells. Under hypoxic conditions, HG further stimulated OPN synthesis and cell proliferation in an additive fashion. In conclusion, hypoxia-induced proliferation of cultured VSM cells is mediated by the stimulation of OPN synthesis involving PKC and p38 MAP kinase. In addition, hypoxia also enhances the effect of HG conditions on both OPN and proliferation of cultured VSM cells, which may have important implications in the development of diabetic atherosclerosis associated with arterial wall hypoxia.

The transcription factor Forkhead Box P3 gene variants affect idiopathic recurrent pregnancy loss.

INTRODUCTION: Forkhead Box P3 (FOXP3) is an essential transcription factor for the induction and development of Tregs. It plays an important role in regulation and suppression of immune responses. We tested whether FOXP3 gene variants are associated with idiopathic recurrent miscarriages (IRM). METHODS: We included 200 women with at least three unexplained spontaneous abortions before twentieth week of gestation and 300 healthy parous women. The detection of genetic variants of rs2232365, and rs5902434 SNPs were carried-out by using polymerase chain reaction (PCR) with sequence-specific primers, while rs3761548 and rs2294021 SNPs were genotyped by PCR followed by RFLP analysis. The logistic odds ratios (ORs) of idiopathic RM risk were estimated with a 95% confidence interval (CI) after maternal age adjustment. Multifactor dimension reduction (MDR) analysis was used to evaluate the potential SNP ∼ SNP interactions. RESULTS: Single marker analysis revealed an increased risk ranged from almost 3-fold-2-fold for rs2232365, rs3761548, rs5902434 and rs2294021 SNPs in IRM cases. The mutant haplotype carriers of rs2232365, rs3761548, rs5902434 and rs2294021 SNPs showed an increased risk of 2.5-fold for IRM cases. Linkage disequilibrium analysis revealed moderate LD between rs2232365, rs3761548, rs5902434 and rs2294021 SNPs. The MDR analysis revealed 6-fold increased risk for IRM cases in four factor models of rs2232365, rs3761548, rs5902434 and rs2294021 SNPs. The maximum testing accuracy, highest cross validation consistency and greater significance was observed in four SNP model. DISCUSSION: These results suggest that variants of FOXP3 SNPs namely; rs2232365, rs3761548, rs5902434 and rs2294021 may be associated with idiopathic RM.

Complex camptopolydactyly: an unusual hand malformation.

Different types of polydactylies and other hand malformations are commonly seen. Here, we describe a very unusual type of hand malformation characterised by campto-polydactyly with totally disorganised configuration of digits. The role of possible genes involved in development of hands and digits is discussed.

Further delineation of a new (Van Den Ende-Gupta) syndrome of blepharophimosis contractural arachnodactyly, and characteristic face.

We report on 2 unrelated Indian girls with blepharophimosis, arachnodactyly, digital contractures which improved spontaneously, elbow deformity, beaked nose, everted lips, and large ears, findings similar to those in 2 cases reported previously by Van Den Ende et al. [1992, Am J Med Genet 42:467-469] and Gupta et al. [1995, J Med Genet 32:809-812], thus delineating a new syndrome of contractural arachnodactyly with characteristic facial anomalies.

Preaxial brachydactyly with abduction of thumbs and hallux varus: a distinct entity.

We describe a father and his daughter who had a unique pattern of preaxial brachydactyly, and unusual facial appearance. Both had short broad abducted thumbs and halluces. The second digits of both hands were also short and broad and those of feet were medially angulated. The radiographic findings were short first metacarpals and first metatarsals and hypoplastic phalanges of first two digits of hands and feet. A similar pattern of brachydactyly was described by Christian et al. [1972: Am J Hum Genet 24:694-701] and Mononen et al. [1992: Am J Med Genet 42: 706-713]. Our patients differ from those described by Christian et al. in that they did not have any mental retardation and from those of Mononen et al. by the absence of short stature and epiphyseal and metaphyseal changes. The heterogeneity of this new type of brachydactyly remains to be resolved.

Pachygyria/hypogenitalism: A monogenic syndrome.

We describe the clinical and neuroimaging findings of two severely retarded boys born to consanguineous parents. This appears to be a monogenic condition of abnormal neuronal migration associated with hypogenitalism. Reports of other monogenic syndromes of neuronal migration abnormalities are reviewed.