Rare genetic diseases in India: Steps toward a nationwide mission program.

Rare genetic diseases are rare by themselves with prevalence of 1 in 25,000, but collectively they are a significant cause of morbidity and mortality. Till date, collectively there are more than 9,000 rare diseases documented, which impose a devastating impact on patients, their families, and the healthcare system, including enormous societal burden. Obtaining a conclusive diagnosis for a patient with a rare genetic disease can be long and gruelling. For some patients it takes months or years to receive a definite diagnosis, and around 50% of the patients remain undiagnosed even with expert clinical and advanced high-end laboratory investigations. Owing to the large population and practice of consanguinity the Indian population is a pool of indigenous variants and unreported phenotypes or diseases. A mission program on pediatric rare diseases is an unparalleled initiative to study unique clinical conditions via the use of latest state-of-art technologies and with the combination of a mulit-omics approach. Our initiative will not only provide diagnosis to patients with rare disease but also build a platform for translational research for rare disease screening, management, and treatment.

Epigenetic interaction of microbes with their mammalian hosts.

The interaction of microbiota with its host has the ability to alter the cellular functions of both, through several mechanisms. Recent work, from many laboratories including our own, has shown that epigenetic mechanisms play an important role in the alteration of these cellular functions. Epigenetics broadly refers to change in the phenotype without a corresponding change in the DNA sequence. This change is usually brought by epigenetic modifications of the DNA itself, the histone proteins associated with the DNA in the chromatin, non-coding RNA or the modifications of the transcribed RNA. These modifications, also known as epigenetic code, do not change the DNA sequence but alter the expression level of specific genes. Microorganisms seem to have learned how to modify the host epigenetic code and modulate the host transcriptome in their favour. In this review, we explore the literature that describes the epigenetic interaction of bacteria, fungi and viruses, with their mammalian hosts.

Whole exome sequencing reveals a mutation in ARMC9 as a cause of mental retardation, ptosis, and polydactyly.

Intellectual disability (ID) refers to deficits in mental abilities, social behavior, and motor skills to perform activities of daily living as compared to peers. Numerous genetic and environmental factors may be responsible for ID. We report on elucidation of molecular basis for syndromic ID associated with ptosis, polydactyly, and MRI features suggestive of Joubert syndrome using homozygosity mapping followed by exome sequencing. The analysis revealed a novel synonymous variation p.T293T (c.879G>A) which leads to a splicing defect in ARMC9 gene. The variant is present in conserved region of ARM domain of ARMC9 protein, which is predicted to form a platform for protein interaction. This domain is likely to be altered in patient due to splicing defect caused by this synonymous variation. Our report of variant in ARMC9 Leading to Joubert syndrome phenotype (JS30), elucidates the genetic heterogeneity of Joubert syndrome, and expands the gene list for ciliopathies.

Complex Camptosynpolydactyly and Mesoaxial synostotic syndactyly with phalangeal reduction are allelic disorders.

Complex Camptosynpolydactyly is an autosomal recessive disorder characterized by complex hand deformities described earlier by us in a consanguineous family. We report on identification of mutations in BHLHA9 gene in this condition. Our results indicate that Complex Camptosynpolydactyly and Mesoaxial synostotic syndactyly with phalangeal reduction (MSSD) are likely to be allelic disorders. © 2016 Wiley Periodicals, Inc.

Identification of Promotor and Exonic Variations, and Functional Characterization of a Splice Site Mutation in Indian Patients with Unconjugated Hyperbilirubinemia.

BACKGROUND: Mild unconjugated hyperbilirubinemia (UH), due to reduced activity of the enzyme uridine diphosphoglucuronate-glucuronosyltransferase family, polypeptide 1 (UGT1A1), is a common clinical condition. Most cases are caused by presence in homozygous form of an A(TA)7TAA nucleotide sequence instead of the usual A(TA)6TAA sequence in promoter region of the UGT1A1 gene. In some cases, other genetic variations have been identified which differ between populations. There is need for more data on such genetic variations from India. METHODS: DNA from subjects with unexplained persistent or recurrent UH was tested for the presence of TA promoter insertions. In addition, all five exons and splicing site regions of UGT1A1 gene were sequenced. Several bioinformatics tools were used to determine the biological significance of the observed genetic changes. Functional analysis was done to look for effect of a splice site mutation in UGT1A1. RESULTS: Of 71 subjects with UH (68 male; median age [range], 26 [16-63] years; serum bilirubin 56 [26-219] µM/L, predominantly unconjugated) studied, 65 (91.5%) subjects were homozygous for A(TA)7TAA allele, five (7.0%) were heterozygous, and one (1.4%) lacked this change. Fifteen subjects with UH had missense exonic single nucleotide changes (14 heterozygous, 1 homozygous), including one subject with a novel nucleotide change (p.Thr205Asn). Bioinformatics tools predicted some of these variations (p.Arg108Cys, p.Ile159Thr and p.Glu463Val) to be deleterious. Functional characterization of an exonic variation (c.1084G>A) located at a splice site revealed that it results in frameshift deletion of 31 nucleotides and premature truncation of the protein. CONCLUSION: Our study revealed several single nucleotide variations in UGT1A1 gene in Indian subjects with UH. Functional characterization of a splice site variation indicated that it leads to disordered splicing. These variations may explain UH in subjects who lacked homozygous A(TA)7TAA promoter alleles.

Novel ABCA12 mutations in harlequin ichthyosis: a journey from photo diagnosis to prenatal diagnosis.

Harequin ichthyosis is a severe autosomal recessive ichthyosis of congenital onset caused by biallelic mutations in the ABCA12 gene. We report two neonates of Indian origin with harlequin ichthyosis. The parents were retrospectively found to have novel mutations in ABCA12 gene after neonatal demise, which helped in providing prenatal diagnosis in subsequent pregnancies.

Alterations of the characteristics of the circadian rest-activity rhythm of cancer in-patients.

The aim of the present study was to evaluate the characteristics of the circadian rest-activity rhythm of cancer patients. Thirty-one in-patients, consisting of 19 males and 12 females, were randomly selected from the Regional Cancer Center, Pandit Jawaharlal Nehru Medical College, Raipur, India. The rest-activity rhythm was studied non-invasively by wrist actigraphy, and compared with 35 age-matched apparently healthy subjects (22 males and 13 females). All subjects wore an Actiwatch (AW64, Mini Mitter Co. Inc., USA) for at least 4-7 consecutive days. Fifteen-second epoch length was selected for gathering actigraphy data. In addition, several sleep parameters, such as time in bed, assumed sleep, actual sleep time, actual wake time, sleep efficiency, sleep latency, sleep bouts, wake bouts, and fragmentation index, were also recorded. Data were analyzed using several statistical techniques, such as cosinor rhythmometry, spectral analysis, ANOVA, Duncan's multiple-range test, and t-test. Dichotomy index (I