Sumita Danda

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.

Effect of Oral Eliglustat on Splenomegaly in Patients With Gaucher Disease Type 1 The ENGAGE Randomized Clinical Trial

IMPORTANCE Gaucher disease type 1 is characterized by hepatosplenomegaly, anemia, thrombocytopenia, and skeletal disease. A safe, effective oral therapy is needed. OBJECTIVE To determine whether eliglustat, a novel oral substrate reduction therapy, safely reverses clinical manifestations in untreated adults with Gaucher disease type 1. DESIGN, SETTING, AND PARTICIPANTS Phase 3, randomized, double-blind, placebo-controlled trial conducted at 18 sites in 12 countries from November 2009 to July 2012 among eligible patients with splenomegaly plus thrombocytopenia and/or anemia. Of 72 patients screened, 40 were enrolled. INTERVENTIONS Patients were stratified by spleen volume and randomized 1:1 to receive eliglustat (50 or 100 mg twice daily; n = 20) or placebo (n = 20) for 9 months. MAIN OUTCOMES AND MEASURES The primary efficacy end point was percentage change in spleen volume in multiples of normal from baseline to 9 months; secondary efficacy end points were change in hemoglobin level and percentage changes in liver volume and platelet count. RESULTS All patients had baseline splenomegaly and thrombocytopenia (mostly moderate or severe), most had mild or moderate hepatomegaly, and 20% had mild anemia. Least-square mean spleen volume decreased by 27.77% (95% CI, -32.57% to -22.97%) in the eliglustat group (from 13.89 to 10.17 multiples of normal) vs an increase of 2.26% (95% CI, -2.54% to 7.06%) in the placebo group (from 12.50 to 12.84 multiples of normal) for an absolute treatment difference of -30.03% (95% CI, -36.82% to -23.24%; P < .001). For the secondary end points, the least-square mean absolute differences between groups all favored eliglustat, with a 1.22-g/dL increase in hemoglobin level (95% CI, 0.57-1.88 g/dL; P < .001), 6.64% decrease in liver volume (95% CI, -11.37% to -1.91%; P = .007), and 41.06% increase in platelet count (95% CI, 23.95%-58.17%; P < .001). No serious adverse events occurred. One patient in the eliglustat group withdrew (non-treatment related); 39 of the 40 patients transitioned to an open-label extension study. CONCLUSIONS AND RELEVANCE Among previously untreated adults with Gaucher disease type 1, treatment with eliglustat compared with placebo for 9 months resulted in significant improvements in spleen volume, hemoglobin level, liver volume, and platelet count. The clinical significance of these findings is uncertain, and more definitive conclusions about clinical efficacy and utility will require comparison with the standard treatment of enzyme replacement therapy as well as longer-term follow-up. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00891202.

Analysis of the WISP3 gene in Indian families with progressive pseudorheumatoid dysplasia.

Progressive pseudorheumatoid dysplasia (PPD) is a progressive skeletal syndrome characterized by stiffness, swelling and pain in multiple joints with associated osteoporosis in affected patients. Radiographically, the predominant features resemble a spondyloepiphyseal dysplasia. Mutations in the WISP3 gene are known to cause this autosomal recessive condition. To date, only a limited number of studies have looked into the spectrum of mutations causing PPD. We report on clinical features and WISP3 mutations in a large series of Indian patients with this rare skeletal dysplasia. Families with at least one member showing clinical and radiologic features of PPD were recruited for the study. Symptoms, signs and radiographic findings were documented in 35 patients from 25 unrelated families. Swelling of small joints of hands and contractures are the most common presenting features. Mutation analysis was carried out by bidirectional sequencing of the WISP3 gene in all 35 patients. We summarize the clinical features of 35 patients with PPD and report on 11 different homozygous mutations and one instance of compound heterozygosity. Eight (c.233G>A, c.340T>C, c.348C>A, c.433T>C, c.682T>C, c.802T>G, c.947_951delAATTT, and c.1010G>A) are novel mutations and three (c.156C>A, c.248G>A, and c.739_740delTG) have been reported previously. One missense mutation (c.1010G>A; p.Cys337Tyr) appears to be the most common in our population being seen in 10 unrelated families. This is the largest cohort of patients with PPD in the literature and the first report from India on mutation analysis of WISP3. We also review all the mutations reported in WISP3 till date.

The Cockayne Syndrome Natural History (CoSyNH) study: clinical findings in 102 individuals and recommendations for care

Purpose:Cockayne syndrome (CS) is a rare, autosomal-recessive disorder characterized by microcephaly, impaired postnatal growth, and premature pathological aging. It has historically been considered a DNA repair disorder; fibroblasts from classic patients often exhibit impaired transcription-coupled nucleotide excision repair. Previous studies have largely been restricted to case reports and small series, and no guidelines for care have been established.Methods:One hundred two study participants were identified through a network of collaborating clinicians and the Amy and Friends CS support groups. Families with a diagnosis of CS could also self-recruit. Comprehensive clinical information for analysis was obtained directly from families and their clinicians.Results and Conclusion:We present the most complete evaluation of Cockayne syndrome to date, including detailed information on the prevalence and onset of clinical features, achievement of neurodevelopmental milestones, and patient management. We confirm that the most valuable prognostic factor in CS is the presence of early cataracts. Using this evidence, we have created simple guidelines for the care of individuals with CS. We aim to assist clinicians in the recognition, diagnosis, and management of this condition and to enable families to understand what problems they may encounter as CS progresses.Genet Med 18 5, 483–493.

Mutations in CDC45, Encoding an Essential Component of the Pre-initiation Complex, Cause Meier-Gorlin Syndrome and Craniosynostosis

DNA replication precisely duplicates the genome to ensure stable inheritance of genetic information. Impaired licensing of origins of replication during the G1 phase of the cell cycle has been implicated in Meier-Gorlin syndrome (MGS), a disorder defined by the triad of short stature, microtia, and a/hypoplastic patellae. Biallelic partial loss-of-function mutations in multiple components of the pre-replication complex (preRC; ORC1, ORC4, ORC6, CDT1, or CDC6) as well as de novo stabilizing mutations in the licensing inhibitor, GMNN, cause MGS. Here we report the identification of mutations in CDC45 in 15 affected individuals from 12 families with MGS and/or craniosynostosis. CDC45 encodes a component of both the pre-initiation (preIC) and CMG helicase complexes, required for initiation of DNA replication origin firing and ongoing DNA synthesis during S-phase itself, respectively, and hence is functionally distinct from previously identified MGS-associated genes. The phenotypes of affected individuals range from syndromic coronal craniosynostosis to severe growth restriction, fulfilling diagnostic criteria for Meier-Gorlin syndrome. All mutations identified were biallelic and included synonymous mutations altering splicing of physiological CDC45 transcripts, as well as amino acid substitutions expected to result in partial loss of function. Functionally, mutations reduce levels of full-length transcripts and protein in subject cells, consistent with partial loss of CDC45 function and a predicted limited rate of DNA replication and cell proliferation. Our findings therefore implicate the preIC as an additional protein complex involved in the etiology of MGS and connect the core cellular machinery of genome replication with growth, chondrogenesis, and cranial suture homeostasis.

Neonatal hearing screening — Experience from a tertiary care hospital in Southern India

ObjectiveTo implement a neonatal hearing screening program using automated auditory brainstem response audiometry in a tertiary care set-up and assess the prevalence of neonatal hearing loss.DesignDescriptive study.SettingTertiary care hospital in Southern India.Participants9448 babies born in the hospital over a period of 11 months.InterventionThe neonates were subjected to a two stage sequential screening using the BERAphone. Neonates suspected of hearing loss underwent confirmatory testing using auditory steady state response audiometry. In addition, serological testing for TORCH infections, and connexin 26 gene was done.Main outcome measuresFeasibility of the screening program, prevalence of neonatal hearing loss and risk factors found in association with neonatal hearing loss.Results164 babies were identified as suspected for hearing loss, but of which, only 58 visited the audiovestibular clinic. Among 45 babies who had confirmatory testing, 39 were confirmed to have hearing loss and were rehabilitated appropriately. 30 babies had one or more risk factors; 6 had evidence of TORCH infection and 1 had connexin 26 gene mutation.ConclusionNeonatal hearing screening using BERA phone is a feasible service. The estimated prevalence of confirmed hearing loss was comparable to that in literature. Overcoming the large numbers of loss to follow-up proves to be a challenge in the implementation of such a program.

GALNS Mutations in Indian Patients With Mucopolysaccharidosis IVA

Mucopolysaccharidosis IV A (Morquio syndrome A, MPS IVA) is a lysosomal storage disease caused by the deficiency of N‐acetylgalactosamine‐6‐sulfatase (GALNS). The mutation spectrum in this condition is yet to be determined in Indians. We aimed to analyze the mutations in the GALNS gene in Asian Indians with MPS IVA. All the exons and the adjacent intronic regions of the gene were amplified and sequenced in sixty‐eight unrelated Indian families. We identified 136 mutant alleles comprising of 40 different mutations. We report twenty‐two novel mutations that comprise of seventeen missense (p.Asn32Thr, p.Leu36Arg, p.Pro52Leu, p.Pro77Ser, p.Cys79Arg, p.His142Pro, p.Tyr191Asp, p.Asn204Thr, p.Gly188Ser, p.Phe216Ser, p.Trp230Cys, p.Ala291Ser, p.Gly317Arg, p.His329Pro, p.Arg386Ser, p.Glu450Gly, p.Cys501Ser), three splice‐site variants (c.120 + 1G > C, c.1003‐3C > G, c.1139 + 1G > A), one nonsense mutation (p.Gln414*) and one frameshift mutation (p.Pro420Leufs*440). Eighteen mutations have been reported earlier. Among these p.Ser287Leu (8.82%), p.Phe216Ser (7.35%), p.Asn32Thr (6.61%) and p.Ala291Ser (5.88%) were the most frequent mutations in Indian patients but were rare in the mutational profiles reported in other populations. These results indicate that the Indian patients may have a distinct mutation spectrum compared to those of other populations. Mutant alleles in exon 1, 7 and 8 accounted for 44.8% of the mutations, and sequencing of these exons initially may be a cost‐effective approach in Asian Indian patients. This is the largest study on molecular analysis of patients with MPS IVA reported in the literature, and the first report from India.

Molecular analyses of novel ASAH1 mutations causing Farber lipogranulomatosis: analyses of exonic splicing enhancer inactivating mutation.

Farber lipogranulomatosis is a rare autosomal recessive lysosomal storage disorder caused by mutations in the ASAH1 gene. In the largest ever study, we identified and characterized ASAH1 mutations from 11 independent Farber disease (FD) families. A total of 13 different mutations were identified including 1 splice, 1 polypyrimidine tract (PPT) deletion and 11 missense mutations. Eleven mutations were exclusive to the Indian population. The IVS6+4A>G splice and IVS5‐16delTTTTC PPT deletion mutations resulted in skipping of exon 6 precluding thereby the region responsible for cleavage of enzyme precursor. A missense mutation (p.V198A) resulted in skipping of exon 8 due to inactivation of an exonic splicing enhancer (ESE) element. This is the first report of mutations affecting PPT and ESE in the ASAH1 gene resulting in FD.

Outcomes after 18 months of eliglustat therapy in treatment-naïve adults with Gaucher disease type 1: The phase 3 ENGAGE trial

Eliglustat, an oral substrate reduction therapy, is a first‐line treatment for adults with Gaucher disease type 1 (GD1) who are poor, intermediate, or extensive CYP2D6 metabolizers (>90% of patients). In the primary analysis of the Phase 3 ENGAGE trial (NCT00891202), eliglustat treatment for 9 months resulted in significant reductions in spleen and liver volumes and increases in hemoglobin concentration and platelet count compared with placebo. We report 18‐month outcomes of patients who entered the trial extension period, in which all patients received eliglustat. Of 40 trial patients, 39 entered the extension period, and 38 completed 18 months. Absolute values and percent change over time were determined for spleen and liver volume, hemoglobin concentration, platelet count, bone mineral density, bone marrow burden, and Gaucher disease biomarkers. For patients randomized to eliglustat in the double‐blind period, continuing treatment with eliglustat for 9 more months resulted in incremental improvement of all disease parameters. For patients randomized to placebo in the double‐blind period, eliglustat treatment during the 9‐month, open‐label period resulted in significant decrease of spleen and liver volumes and significant increase of hemoglobin and platelets, with a similar rate of change to patients who had received eliglustat in the double‐blind period. Eliglustat treatment was also associated with improvement in bone marrow burden score, bone mineral density, and established biomarkers of Gaucher disease, including reduction of the bioactive lipid, glucosylsphingosine. These findings underscore the efficacy of eliglustat in treatment‐naïve patients. Eliglustat was well‐tolerated, and there were no new safety concerns with longer‐term exposure.

A descriptive analysis of 14 cases of progressive-psuedorheumatoid-arthropathy of childhood from south India: Review of literature in comparison with Juvenile Idiopathic Arthritis

BACKGROUND Progressive-psuedorheumatoid-arthropathy of childhood (PPAC) is an autosomal recessive single gene skeletal dysplasia involving joints. The gene attributed to its cause is WNT1-inducible-signaling pathway protein3 (WISP3). OBJECTIVE To study the clinical and radiographic presentation of PPAC in Indian patients and to compare with described features of PPAC and Juvenile Idiopathic Arthritis (JIA) from published literature. METHODS All cases (n = 14) of PPAC seen in the Rheumatology and Clinical Genetics outpatient clinic between 2008 and 2011 with classical, clinical, and radiological features were studied. The demographic and clinical data were obtained from medical records of the outpatient visits. RESULTS Slight female preponderance (57%) and history of consanguinity in parents (43%) was observed in this group. The median age at onset was 4.5 years (range from birth to 9 years of age). Early presentation below the age of 3 years was seen in 3/14 patients (21%) in this group. The growth of all the patients fell below the 3rd percentile for the age. Historically, hip joint involvement was the most common presenting feature; however, elbow, wrist, knees, feet, spine, shoulder joints and small joints, namely proximal interphalangeal (PIP), distal interphalangeal (DIP), metacarpophalangeal (MCP), metatarsophalangeal joints (MTP), and interphalangeal joints (IP) of the feet, were also involved, either clinically or radiologically in varying proportions. Platyspondyly was noted in all. Molecular analysis of the WISP3 gene identified mutations in all the 5 individuals in whom it was done. CONCLUSION This descriptive case series of PPAC from India reports distinctly differentiating clinical, radiological, and molecular markers in contrast with classically described features of JIA, its mimic. Early presentation (age of onset below 3 years) with involvement of interphalangeal joints seen in three patients (21%) was a unique finding, with missense WISP3 gene mutations in all of them. Timely diagnosis of this entity can spare the patient from unnecessary investigations and toxic medications.