IndiGenomes: a comprehensive resource of genetic variants from over 1000 Indian genomes.

With the advent of next-generation sequencing, large-scale initiatives for mining whole genomes and exomes have been employed to better understand global or population-level genetic architecture. India encompasses more than 17% of the world population with extensive genetic diversity, but is under-represented in the global sequencing datasets. This gave us the impetus to perform and analyze the whole genome sequencing of 1029 healthy Indian individuals under the pilot phase of the 'IndiGen' program. We generated a compendium of 55,898,122 single allelic genetic variants from geographically distinct Indian genomes and calculated the allele frequency, allele count, allele number, along with the number of heterozygous or homozygous individuals. In the present study, these variants were systematically annotated using publicly available population databases and can be accessed through a browsable online database named as 'IndiGenomes' http://clingen.igib.res.in/indigen/. The IndiGenomes database will help clinicians and researchers in exploring the genetic component underlying medical conditions. Till date, this is the most comprehensive genetic variant resource for the Indian population and is made freely available for academic utility. The resource has also been accessed extensively by the worldwide community since it's launch.

Cancer awareness, diagnosis and treatment needs in Mizoram, India: evidence from 18 years trends (2003-2020).

Background: Despite being the second least populated state, Mizoram exhibits the highest incidence rate of cancer in India. Its inhabitants, constituting an endogamous and isolated population, have embraced their own distinct culture, way of life and dietary preferences, setting them apart from the rest of mainland India. In 2003, the Mizoram Population Based Cancer Registry (PBCR) was established under the auspices of the National Centre for Disease Informatics and Research (NCDIR), a division of the Indian Council of Medical Research (ICMR), in collaboration with the Department of Health & Family Welfare of the Government of Mizoram, India. Methods: Cancer incidence and mortality data were extracted from the Mizoram PBCR spanning the years 2003-2020. The Age Standardized Incidence Rate (ASIR) and Age Standardized Mortality Rate (ASMR) were computed per 100,000 individuals, utilizing Segi's World Standard Population as the benchmark. The trajectory of these changes was analysed employing the Joinpoint Regression Analysis Program, Version 4.9.1.0.13, to unveil the Annual Percent Change (APC) with a 95% Confidence Interval and a Significance test (p < 0.05) using Monte Carlo Permutation. The resulting graphical visualizations were generated using Flourish Studio.15. Findings: The overall ASIR for all cancer sites among men was 197.2 per 100,000, while for women, it was 164.9 per 100,000. Among men, the most prevalent cancer site was the Stomach (ASIR = 41.4), followed by Head & Neck, Lung, Oesophagus, Colorectal, Liver, Urinary, Non-Hodgkin's Lymphoma and Prostate cancers. Conversely, among women, Lung cancer exhibited the highest incidence (ASIR = 26.7), succeeded by Cervical, Breast, Stomach, Head & Neck, Colorectal, Oesophagus, Liver and Ovarian cancers. Stomach cancer emerged as the leading cause of death among men (ASMR = 22.6) and among women, Lung cancer held the highest ASMR (15.9). Joinpoint regression analysis revealed a rising trend in incidence and mortality over time for overall cancer sites. Among the primary cancer sites contributing to incidence and mortality, an increase in APC was observable for all, except Stomach cancer, in both men and women. The diagnostic approach, except for cases of cancer with unknown primary sites, involved a microscopic method. Interpretation: This cross-sectional study examines PBCR reports spanning from 2003 to 2020, shedding light on a consistent uptick in cancer incidence and mortality trends in Mizoram. Stomach cancer emerges as the most prevalent and primary cause of cancer-related deaths among men, while Lung cancer takes a parallel role in women. The elevated cancer incidence and the growing trend among younger generations might stem from the static lifestyle and dietary patterns prevalent within the endogamous tribal population, potentially contributing to a genetic predisposition. The escalation in mortality rates could be attributed to a dearth of specialized diagnostic facilities and skilled human resources, treatment strategies guided by genomic research and transportation challenges. This underscores the urgent requirement for comprehensive scientific exploration across diverse facets. The implementation of easily accessible diagnostic facilities in proximity and genetic testing for pharmacogenomics to enhance prognoses would also aid in mitigating the burden and advancing the healthcare system's effectiveness. Funding: Population Based Cancer Registry (PBCR) was supported by National Centre for Disease Informatics and Research (NCDIR) of the Indian Council of Medical Research (ICMR), India.

Whole exome sequencing of pediatric leukemia reveals a novel InDel within FLT-3 gene in AML patient from Mizo tribal population, Northeast India.

BACKGROUND: Leukemia is the most common type of cancer in pediatrics. Genomic mutations contribute towards the molecular mechanism of disease progression and also helps in diagnosis and prognosis. This is the first scientific mutational exploration in whole exome of pediatric leukemia patients from a cancer prone endogamous Mizo tribal population, Northeast India. RESULT: Three non-synonymous exonic variants in NOTCH1 (p.V1699E), MUTYH (p.G143E) and PTPN11 (p.S502P) were found to be pathogenic. A novel in-frame insertion-deletion within the juxtamembrane domain of FLT3 (p.Tyr589_Tyr591delinsTrpAlaGlyAsp) was also observed. CONCLUSION: These unique variants could have a potential mutational significance and these could be candidate genes in elucidating the possibility of predisposition to cancers within the population. This study merits further investigation for its role in diagnosis and prognosis and also suggests the need for population wide screening to identify unique mutations that might play a key role towards precision medicine.

Whole exome sequencing identifies the novel putative gene variants related with type 2 diabetes in Mizo population, northeast India.

The contribution of genes towards T2D development varies among different population groups across the world. It has been reported that a number of loci involved in T2D susceptibility are common across certain population groups, but ethnicity specific variants are also observed. The population of Mizoram has an independent ethnic identity and there are no scientific records about the history of the Mizo people; which makes this ethnic group unique and interesting to study. The aim of the study focuses on the identification of the gene variants which may contribute to T2D susceptibility in Mizo-Mongloid ethnic tribe of North east India through whole exome sequencing. The variants like 328G > C (KRT18), 997G > T (CYP4A11), 2368 T > C (SLC4A3), 508G > A (SLC26A5), 1659C > T (KCNS1), 650C > A (ABCD1) 821A > T (YTHDC2), 931G > T (PINX1), 3280C > A (TNRC6A), 48C > A(TACO1), 6035A > T(LAMA1), 805C > A(ACP7) and 806A > G(ACP7) variants were not reported for any disease in the database and were found to be pathogenic in different insilico analysis softwares. The changes in protein stability upon mutation has been predicted where 35.71% increases the stability of the protein, while 64.28% of the variants decrease the stability of the protein. These findings present the population specific variants which might involve in the susceptibility to T2D in Mizo population. Further, in this study some gene variants have contribution as a possible diagnostic or prognostic marker for other diseases as well, which suggests the need for performing association analysis for different disease manifestations in Mizo population in the near future.

Pharmacogenomic landscape of COVID-19 therapies from Indian population genomes.

Aim: Numerous drugs are being widely prescribed for COVID-19 treatment without any direct evidence for the drug safety/efficacy in patients across diverse ethnic populations. Materials & methods: We analyzed whole genomes of 1029 Indian individuals (IndiGen) to understand the extent of drug-gene (pharmacogenetic), drug-drug and drug-drug-gene interactions associated with COVID-19 therapy in the Indian population. Results: We identified 30 clinically significant pharmacogenetic variants and 73 predicted deleterious pharmacogenetic variants. COVID-19-associated pharmacogenes were substantially overlapped with those of metabolic disorder therapeutics. CYP3A4, ABCB1 and ALB are the most shared pharmacogenes. Fifteen COVID-19 therapeutics were predicted as likely drug-drug interaction candidates when used with four CYP inhibitor drugs. Conclusion: Our findings provide actionable insights for future validation studies and improved clinical decisions for COVID-19 therapy in Indians.

Genetic epidemiology of autoinflammatory disease variants in Indian population from 1029 whole genomes.

BACKGROUND: Autoinflammatory disorders are the group of inherited inflammatory disorders caused due to the genetic defect in the genes that regulates innate immune systems. These have been clinically characterized based on the duration and occurrence of unprovoked fever, skin rash, and patient's ancestry. There are several autoinflammatory disorders that are found to be prevalent in a specific population and whose disease genetic epidemiology within the population has been well understood. However, India has a limited number of genetic studies reported for autoinflammatory disorders till date. The whole genome sequencing and analysis of 1029 Indian individuals performed under the IndiGen project persuaded us to perform the genetic epidemiology of the autoinflammatory disorders in India. RESULTS: We have systematically annotated the genetic variants of 56 genes implicated in autoinflammatory disorder. These genetic variants were reclassified into five categories (i.e., pathogenic, likely pathogenic, benign, likely benign, and variant of uncertain significance (VUS)) according to the American College of Medical Genetics and Association of Molecular pathology (ACMG-AMP) guidelines. Our analysis revealed 20 pathogenic and likely pathogenic variants with significant differences in the allele frequency compared with the global population. We also found six causal founder variants in the IndiGen dataset belonging to different ancestry. We have performed haplotype prediction analysis for founder mutations haplotype that reveals the admixture of the South Asian population with other populations. The cumulative carrier frequency of the autoinflammatory disorder in India was found to be 3.5% which is much higher than reported. CONCLUSION: With such frequency in the Indian population, there is a great need for awareness among clinicians as well as the general public regarding the autoinflammatory disorder. To the best of our knowledge, this is the first and most comprehensive population scale genetic epidemiological study being reported from India.

Pediatric leukemia could be driven predominantly by non-synonymous variants in mitochondrial complex V in Mizo population from Northeast India.

Leukemia is the most common childhood malignancy and studies had been carried out with promising revelations in its diagnosis and prognosis. However, majority of the studies are focused on nuclear alterations, while mitochondrial mutations are not well studied. Although there are studies of mitochondrial mutations in the adult leukemias, it does not represent the same for childhood malignancy. This is the first scientific report on the mtDNA mutational pattern of pediatric leukemic cases from a endogamous tribal population in Northeast India. ATP6 involved in the Complex V was found to be more altered with respect to the Non-synonymous variants. mtDNA variations in the non-coding region (D-Loop - g.152 T>C) and in the coding region (MT-ND2, g.4824 A>G, p.T119A) showed a maternal inheritance which could reveal a genetic predisposition with lower penetrance. D-Loop variant (g.152 T>C) could be a diagnostic marker in accordance with previous report but is in contrast to pertaining only in AML - M3 subtype rather was found across in myeloid malignancies.