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South Asia is home for more than a billion people culturally structured into innumerable groups practicing different levels of endogamy. Linguistically South Asia is broadly characterized by four major language families which has served as access way for disentangling the genetic makings of South Asia. In this review we shall give brief account on the recent developments in the field. Advances are made in two fronts simultaneously. Whole genome characterisation of many extant South Asians paint the picture of the genetic diversity and its implications to health-care. On the other hand ancient DNA studies, which are finally reaching South Asia, provide new incites to the demographic history of the subcontinent. Before the spread of agriculture, South Asia was likely inhabited by hunter-gatherer groups deriving much of their ancestry from a population that split from the rest of humanity soon after expanding from Africa. Early Iranian agriculturalists mixing with these local hunter-gatherers probably formed the population that flourished during the blossoming of the Indus Valley Civilisation. Further admixture with the still persisting HG groups and population(s) from the Eurasian Steppe, formed the two ancestral populations (ANI and ASI), the north-south mixing pattern of whom is known today as the 'Indian Cline'. Studies on natural selection in South Asia have so far revealed strong signals of sweeps that are shared with West Eurasians. Future studies will have to fully unlock the aDNA promise for South Asia. [ABSTRACT FROM AUTHOR]

Despite rapidly growing understandings and dependency on single nucleotide polymorphisms (SNPs), highly variable autosomal short tandem repeats (STRs) are still regarded as the most established method to differentiate individuals at forensic level. Here with large number of various ethnic groups we undertook this study to reveal the genetic structure of the most densely populated part of South Asia i.e. the Bangladesh. The purpose of this work was to estimate population parameters based on the allele frequencies obtained for 15 polymorphic autosomal STR loci investigated in caste and tribal populations from Bangladesh ( n = 706). We compared the results in a broader context by merging 24 different populations of Asia to pertain their affinity. Various statistical analyses suggested a clear cut demarcation of tribal and non-tribal in Bangladesh. Moreover, beside the phylogenetic structure of the studied populations, it is found that the mean heterozygosity value was highest among the populations of Bangladesh, likely because of gene flow from different directions. However, Tonchangya, Adi and Khumi showed sign of genetic isolation and reduced diversity, possibly as a result of genetic drift and/or strong founder effects working on small endogamous populations. [ABSTRACT FROM AUTHOR]

Abstract: History has well documented the execution of Queen Ketevan of Georgia by the Persian Emperor of modern day Iran. Based on historical records, in 1624 two Augustinian friars unearthed the queen's remains and one of them brought the relic to the St. Augustine convent in Goa, India. We carried out ancient DNA analysis on the human bone remains excavated from the St. Augustine convent by sequencing and genotyping of the mitochondrial DNA. The investigations of the remains revealed a unique mtDNA haplogroup U1b, which is absent in India, but present in Georgia and surrounding regions. Since our genetic analysis corroborates archaeological and literary evidence, it is likely that the excavated bone belongs to Queen Ketevan of Georgia. [Copyright &y& Elsevier]

SARS-CoV-2, the causative agent for COVID-19, an ongoing pandemic, engages the ACE2 receptor to enter the host cell through S protein priming by a serine protease, TMPRSS2. Variation in the TMPRSS2 gene may account for the disparity in disease susceptibility between populations. Therefore, in the present study, we have used next-generation sequencing (NGS) data of world populations from 393 individuals and analyzed the TMPRSS2 gene using a haplotype-based approach with a major focus on South Asia to study its phylogenetic structure and their haplotype sharing among various populations worldwide. Our analysis of phylogenetic relatedness showed a closer affinity of South Asians with the West Eurasian populations therefore, host disease susceptibility and severity particularly in the context of TMPRSS2 will be more akin to West Eurasian instead of East Eurasian. This is in contrast to our prior study on the ACE2 gene which shows South Asian haplotypes have a strong affinity towards West Eurasians. Thus ACE2 and TMPRSS2 have an antagonistic genetic relatedness among South Asians. Considering the significance of the TMPRSS2 gene in the SARS-CoV-2 pathogenicity, COVID-19 infection and intensity trends could be directly associated with increased expression therefore, we have also tested the SNPs frequencies of this gene among various Indian state populations with respect to the case fatality rate (CFR). Interestingly, we found a significant positive association between the rs2070788 SNP (G Allele) and the CFR among Indian populations. Further our cis eQTL analysis of rs2070788 shows that the GG genotype of the rs2070788 tends to have a significantly higher expression of TMPRSS2 gene in the lung compared to the AG and AA genotypes thus validating the previous observation and therefore it might play a vital part in determining differential disease vulnerability. We trust that this information will be useful in understanding the role of the TMPRSS2 variant in COVID-19 susceptibility and using it as a biomarker may help to predict populations at risk. • Variation in the TMPRSS2 gene may account for the difference in COVID-19 vulnerability among various populations. • A strong association between the rs2070788 SNP (G Allele) and the case fatality rate among the Indian populations. • rs2070788(G) allele is associated with higher TMPRSS2 gene expression in the lungs. • South Asians show a closer genetic affinity for the TMPRSS2 gene with the West Eurasians. • The antagonistic genetic relatedness between ACE2 and TMPRSS2 gene among South Asians. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic resulted in multiple waves of infection worldwide. The large variations in case fatality rate among different geographical regions suggest that the human susceptibility against this virus varies substantially. Several studies from different parts of the world showed a significant association of ABO blood group and COVID-19 susceptibility. It was demonstrated that individuals with blood group O are at the lower risk of coronavirus infection. To establish the association of ABO blood group in SARS-CoV-2 susceptibility, we for the first time analysed SARS-CoV-2 neutralising antibodies among 509 individuals, collected from three major districts of Eastern Uttar Pradesh region of India. Interestingly, we found neutralising antibodies in a significantly higher percentage of people with blood group AB (0.36) followed by B (0.31), A (0.22) and lowest in people with blood group O (0.11). We further estimated that people with blood group AB are at comparatively higher risk of infection than other blood groups. Thus, among the asymptomatic SARS-CoV-2 recovered people blood group AB has highest, whilst individuals with blood group O has lowest risk of infection. [ABSTRACT FROM AUTHOR]