Association of Low Birth Weight with the Risk of Childhood Stunting in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis.

BACKGROUND: Stunting is an important predictor of growth and development of children under 5 years of age, and it remains the significant problem in LMIC. However, LBW emerges as risk factor, but its association with LMIC needs attention. OBJECTIVE: This systematic review and meta-analysis aimed to investigate the association of low birth weight with the risk of childhood stunting among the age group of 0-5 years in LMICs. METHODS: PubMed, Google Scholar, MEDLINE, Embase, and Web of Science databases were searched from January 1, 2010 untill December 20, 2021. Cross-sectional, cohort, and case-control study designs were included in the meta-analyses. The pooled odds ratio with a 95% confidence interval was reported considering the random-effects and the quality-effects models. The subgroup analysis and meta-regression were conducted for study design, geographical location, and sample size. RESULTS: Low birth weight was associated with >2-fold increased risk of childhood stunting (pooled OR: 2.32; 95% CI, 2.05-2.62). Asian studies have shown relatively higher risk than African studies in stratified analyses. The cohort studies predicted a higher risk of childhood stunting, followed by case-control and cross-sectional study designs, and the sample size stratification showed that studies with sample size <1,000 predicted much higher risk than relatively to the studies with sample size >1,000. The meta-regression was performed in all three subgroups, but none of the models appeared significant. CONCLUSION: This meta-analysis confirmed the association of low birth weight with the higher risk of childhood stunting among the 0-5 years' age group and suggests a moderately higher risk in Asia as compared to Africa.

Donor-Derived Cell-Free DNA as a Non-Invasive Biomarker for Graft Rejection in Kidney Transplant Recipients: A Prospective Study among the Indian Population.

Monitoring graft health and detecting graft rejection is crucial for the success of post-transplantation outcomes. In Western countries, the use of donor-derived cell-free DNA (dd-cfDNA) has gained widespread recognition as a diagnostic tool for kidney transplant recipients. However, the role of dd-cfDNA among the Indian population remains unexplored. The recipients were categorized into two groups: the post-transplant recipient (PTR) group (n = 16) and the random recipient (RR) group (n = 87). Blood samples were collected daily from the PTR group over a 7-day period, whereas the RR group's samples were obtained at varying intervals. In this study, we used a targeted approach to identify dd-cfDNA, which eliminated the need for genotyping, and is based on the minor allele frequency of SNP assays. In the PTR group, elevated dd-cfDNA% levels were observed immediately after transplantation, but returned to normal levels within five days. Within the RR group, heightened serum creatinine levels were directly proportional to increased dd-cfDNA%. Sixteen recipients were advised to undergo biopsy due to elevated serum creatinine and other pathological markers. Among these sixteen recipients, six experienced antibody-mediated rejection (ABMR), two exhibited graft dysfunctions, two had active graft injury, and six (37.5%) recipients showed no rejection (NR). In cases of biopsy-proven ABMR and NR, recipients displayed a mean ± SD dd-cfDNA% of 2.80 ± 1.77 and 0.30 ± 0.35, respectively. This study found that the selected SNP assays exhibit a high proficiency in identifying donor DNA. This study also supports the use of dd-cfDNA as a routine diagnostic test for kidney transplant recipients, along with biopsies and serum creatinine, to attain better graft monitoring.

Genetic associations of TMEM154, PRC1 and ZFAND6 loci with type 2 diabetes in an endogamous business community of North India.

BACKGROUND: More than 250 loci have been identified by genome-wide scans for type 2 diabetes in different populations. South Asians have a very different manifestation of the diseases and hence role of these loci need to be investigated among Indians with huge burden of cardio-metabolic disorders. Thus the present study aims to validate the recently identified GWAS loci in an endogamous caste population in North India. METHODS: 219 T2D cases and 184 controls were recruited from hospitals and genotyped for 15 GWAS loci of T2D. Regression models adjusted for covariates were run to examine the association for T2D and fasting glucose levels. RESULTS: We validated three variants for T2D namely, rs11634397 at ZFAND6 (OR = 3.05, 95%CI = 1.02-9.19, p = 0.047) and rs8042680 at PRC1 (OR = 3.67, 95%CI = 1.13-11.93, p = 0.031) showing higher risk and rs6813195 at TMEM154 (OR = 0.28, 95%CI = 0.09-0.90, p = 0.033) showing protective effect. The combined risk of 9 directionally consistent variants was also found to be significantly associated with T2D (OR = 1.91, 95%CI = 1.18-3.08, p = 0.008). One variant rs10842994 at KLHDC5 was validated for 9.15mg/dl decreased fasting glucose levels (SE = -17.25-1.05, p = 0.027). CONCLUSION: We confirm the role of ZFAND6, PRC1 and TMEM154 in the pathophysiology of type 2 diabetes among Indians. More efforts are needed with larger sample sizes to validate the diabetes GWAS loci in South Asian populations for wider applicability.

Women infertility and common mental disorders: A cross-sectional study from North India.

BACKGROUND: Infertility is a very distressing condition. It is often associated with long-term stress, which can emerge as anxiety and depression. AIM: To understand the effect of socio-demographic variables, reproductive trajectories, and lifestyle variables on stress, depression, and anxiety independently and to understand the relationship of psychological variables with each other among infertile and fertile women. METHODS: This cross-sectional study recruited 500 women which included 250 primary infertile cases and 250 age-matched fertile controls of the age group 22-35 years. A pretested modified interview schedule was administered which included demographic variables, lifestyle variables, and reproductive trajectories. In addition, psychological tools like PSS, GAD-7, and PHQ-9 were used to collect the data pertaining to Stress, anxiety, and depression, respectively. Data analysis was performed with the statistical software version SPSS, IBM version 24. RESULTS: Infertile women are more prone to various psychological disorder (stress, anxiety and depression). None of the demographic and lifestyle variables were associated with stress, anxiety, and depression among infertile women. Only reproductive trajectories were found to be causing stress, anxiety, and depression respectively among infertile women. In addition, stress is leading to both anxiety and depression among infertile women but only to depression in fertile women. CONCLUSION: Infertile women should be counselled by medical experts regarding reproductive trajectories. Infertile couples should be guided and counselled to incorporate mental health screening and treatment in their routine check-up.

MTR, MTRR and CBS Gene Polymorphisms in Recurrent Miscarriages: A Case Control Study from North India.

Background: According to various epidemiological studies, the aetiology of recurrent miscarriages (RMs) is multifactorial. The goal of this study is to learn more about the link between genetic polymorphisms and RM. Aim: To evaluate the association of 5-Methytetrahydrofolate-Homocysteine Methyltransferase (MTR) A2756G, 5-Methytetrahydrofolate-Homocysteine Methyltransferase Reductase (MTRR) A66G and cystathionine beta-synthase (CBS) 844INS68 genetic polymorphisms with RM and also to understand the combined effect of the selected genotypes. Study Setting and Design: This was a hospital-based, case-control, observational study. Materials and Methods: A total of 516 participants were recruited in the present study, of which 200 RM cases and 258 controls were included in the present study. Fasting blood sample (~5ml) was drawn from all the participants and were screened for genetic polymorphisms of MTR A2756G, MTRR A66G and CBS 844INS68. Statistical Analysis: The frequency, odd's ratio and Hardy-Weinberg equilibrium were evaluated. SPSS (version 21.0) was used for the data analysis. Results: MTR A2756G genetic polymorphism was not associated with the risk of RM. The ancestral allele of MTRR A66G and the mutant allele of CBS 844INS68 was causing an increased risk of more than two folds for RM. CBS 844INS68 in combination with MTR A2756G was found to pose an increased risk of more than two folds for RM. Conclusion: Genetic polymorphisms particularly MTRR A66G and CBS 844INS68 seems to be elevating the risk and hence making women susceptible for RM.

Genetic underpinnings of lung function and COPD.

Spirometry based measurement of lung function is a global initiative for chronic obstructive lung disease (GOLD) standard to diagnose chronic obstructive pulmonary disease (COPD), one of the leading causes of mortality worldwide. The environmental and behavioural risk factors for COPD includes tobacco smoking, air pollutants and biomass fuel exposure, which can induce one or more abnormal lung function patterns. While smoking remains the primary risk factor, only 15-20% smokers develop COPD, indicating that the genetic factors are also likely to play a role. According to the study of Global Burden of Disease 2015, ∼174 million people across the world have COPD. From a comprehensive literature search conducted using the 'PubMed' and 'GWAS Catalogue' databases, and reviewing the literature available, only a limited number of studies were identified which had attempted to investigate the genetics of COPD and lung volumes, implying a huge research gap. With the advent of genomewide association studies several genetic variants linked to lung function and COPD, like HHIP, HTR4, ADAM19 and GSTCD etc., have been found and validated in different population groups, suggesting their potential role in determining lung volume and risk for COPD. This article aims at reviewing the present knowledge of the genetics of lung function and COPD.

Prevalence of cardiovascular risk factors among tribal and non-tribal populations with East Asian Ancestry from North East India.

OBJECTIVES: The distribution of hypertension, type 2 diabetes, dyslipidemia, and obesity variables were studied among tribal and non-tribal populations with East Asian ancestry from northeast India. METHODS: Data pertaining to somatometric measurements, blood pressure, lipid profile, and fasting blood glucose were collected from 1916 participants (Mizo-422, Liangmai-352, and Meitei-1142) of both sexes older than 18 years. Two-way ANOVA and chi square analysis were done to understand the inter-population prevalence differences. RESULTS: Differential distribution of obesity variables, hypertension, type 2 diabetes, and dyslipidemia was observed among the three populations. CONCLUSIONS: Population-specific prevalence studies need to be conducted to develop population-specific health strategies, specifically in countries like India with huge diversity.

Gestational route to healthy birth (GaRBH): protocol for an Indian prospective cohort study.

INTRODUCTION: Pregnancy is characterised by a high rate of metabolic shifts from early to late phases of gestation in order to meet the raised physiological and metabolic needs. This change in levels of metabolites is influenced by gestational weight gain (GWG), which is an important characteristic of healthy pregnancy. Inadequate/excessive GWG has short-term and long-term implications on maternal and child health. Exploration of gestational metabolism is required for understanding the quantitative changes in metabolite levels during the course of pregnancy. Therefore, our aim is to study trimester-specific variation in levels of metabolites in relation to GWG and its influence on fetal growth and newborn anthropometric traits at birth. METHODS AND ANALYSIS: A prospective longitudinal study is planned (start date: February 2018; end date: March 2023) on pregnant women that are being recruited in the first trimester and followed in subsequent trimesters and at the time of delivery (total 3 follow-ups). The study is being conducted in a hospital located in Bikaner district (66% rural population), Rajasthan, India. The estimated sample size is of 1000 mother-offspring pairs. Information on gynaecological and obstetric history, socioeconomic position, diet, physical activity, tobacco and alcohol consumption, depression, anthropometric measurements and blood samples is being collected for metabolic assays in each trimester using standardised methods. Mixed effects regression models will be used to assess the role of gestational weight in influencing metabolite levels in each trimester. The association of maternal levels of metabolites with fetal growth, offspring's weight and body composition at birth will be investigated using regression modelling. ETHICS AND DISSEMINATION: The study has been approved by the ethics committees of the Department of Anthropology, University of Delhi and Sardar Patel Medical College, Rajasthan. We are taking written informed consent after discussing the various aspects of the study with the participants in the local language.

Genetics of obesity and its measures in India.

Obesity is one of the largest global health problems associated with increased morbidity and mortality mediated by its association with several other metabolic disorders. The interaction between the genes and environment plays an important role in the manifestation of obesity. Despite a high heritability (40-70%) of obesity, the search for genetic variants associated with obesity susceptibility has been a challenging task. To date, limited studies have been conducted in India, restricted to the validation of few genetic variants identified by genomewide association studies. In this critical review, we sought to examine the current knowledge of genetic basis of obesity and its measures in the Indian population. A comprehensive literature search was performed using 'PubMed', 'Medline' and 'IndMed' databases to search for citations published until 31st May 2017, using the key terms as 'Genetics' AND 'obesity' AND 'India'. We identified 48 potential studies which fulfilled the eligibility criteria. The findings indicated that FTO, MC4R, TNF-α, PPAR-γ , UCP1, UCP2, LPL, LEPR, AMD1, IL6, APOE, ADIPOQ, DOK5, INSIG2, PBEF1, IL6R, Myostatin, CXCR4, HHEX, IRX3, POMC, NGN3, FOXA2, MTR, TCN and CHDH are some of the important genes studied among the Indian population. Importantly, the role of sexual dimorphism in the genetic regulation of obesity and body fat distribution was also reported in a few studies. Further, seven biological pathways have been identified that contribute to obesity pathogenesis in India. In conclusion, further exploration of pathway-based research on genetics of obesity can be useful for better understanding the pathophysiology of obesity in India.

Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism among Gaddi tribe of Indian state of Himachal Pradesh.

BACKGROUND: Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism has been suggested to be positively associated with several disorders. Distribution of the mutant T-allele varies in ethnic and geographical populations of the world. AIM: The aim of the present study was to investigate the distribution of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in a transhumant (Gaddi) tribal population of Himachal Pradesh dwelling at high and middle altitude and exposed to strong ultraviolet radiation. METHOD AND RESULTS: A total of 486 samples (141 males and 345 females) were randomly enrolled from the individuals aged 25-75 years who were unrelated up to first cousin. Among Gaddis, genotype frequencies of CC, CT and TT were 67.90%, 27.78% and 4.32%, respectively. Among males and females distribution of genotype frequencies also followed a similar trend. The studied population was in Hardy-Weinberg equilibrium (χ(2 )= 2.213, df = 1, p = 0.136). Frequency of mutant T-allele in the Gaddi population was found to be 0.183, which might be due to European ancestry, endogamous nature and selection.

MTHFR C677T polymorphism, folate, vitamin B12 and homocysteine in recurrent pregnancy losses: a case control study among North Indian women.

AIM: The present study attempts to understand the role of methylenetetrahydrofolate reductase C677T (MTHFR C677T) in recurrent pregnancy losses in North Indian women because of hyperhomocysteinemia in light of serum folate and vitamin B12. METHODS: One hundred and seven women with three or more consecutive unexplained recurrent pregnancy losses and 343 women with two or more successful and uncomplicated pregnancies were recruited. Plasma homocysteine, serum folate and vitamin B12 were analyzed using chemiluminescence. MTHFR C677T detection was completed in all subjects. RESULTS: MTHFR genotypic distribution among cases and controls showed no significant difference (P=0.409). However, MTHFR C677T polymorphism was found to be significantly associated with increased homocysteine in the case group (P=0.031). Hyperhomocysteinemia and vitamin B12 deficiency were found to be significant risk factors for recurrent pregnancy loss (RPL) (OR=7.02 and 16.39, respectively). Folate deficiency was more common in controls (63.47%) as compared to the case group (2.56%). CONCLUSION: Low vitamin B12 increases homocysteine, specifically among T allele carrying case mothers, suggesting T allele is detrimental with B12 deficiency. The study emphasizes the importance of vitamin B12 in the prevention of RPL in North Indian women.

Dopamine D2 receptor and ankyrin repeat and kinase domain containing 1 genes among the two linguistically distinct tribal populations of Ranchi district, Jharkhand, India.

In the recent years, haplotype studies have emerged as a critical tool for studying the human migratory patterns. Dopamine D2 receptor (DRD2) and Ankyrin Repeat and Kinase Domain Containing 1 (ANKK1) genes, which also bear specific clinical implications in various neuropsychiatric and behavioural/addictive disorders, are significant nuclear DNA markers for studying human genome diversity. The present study was conducted in order to understand the distribution pattern of the three DRD2 and ANKK1 TaqI sites and also the frequencies of their haplotypes among Oraons (n = 48) and Mundas (n = 50)--the two linguistically distinct tribal population groups of Jharkhand. The phylogenetic inference was drawn through the statistical comparisons of the present DRD2 and ANKK1 TaqI site data with the available data from population groups belonging to other parts of India and also rest of the world (ALFRED Database). All the three TaqI sites were found to be polymorphic among Oraons and Mundas with relatively high average heterozygosities. Oraons exhibited a comparatively higher frequency of the ancestral B2D2A1 haplotype (0.356) than the Mundas (0.193). Significant and higher linkage disequilibrium (LD) values between all three sites were observed among Mundas which is indicative of admixture, whereas Oraons exhibited non significant and low LD values. The presence of ancestral haplotype B2D2A1 in higher frequency and lower and non-significant LD among Oraons suggest that they might be the older inhabitants in the region though the major limitation of the study is small sample size which might have introduced bias in the accuracy of the calculated pairwise LD for the three polymorphic sites.

Genetic thromobophilia in pregnancy: a case-control study among North Indian women.

In the present study, an attempt is made to understand the role of genetic thrombophilias i.e. MTHFR C677T and FVL in the causation of various pregnancy complications like pregnancy induced hypertension (PIH), recurrent abortions, intra-uterine growth retardation (IUGR) and intra-uterine death on the whole and also individually along with the comparative assessment of pathophysiological basis of various pregnancy complications via the genetic proximities. One thousand and eleven (1,011) women of reproductive age group were recruited in the present study comprising various complications and controls. Recruitment criteria for all the pregnancy complications and controls was made and followed strictly. MTHFR C677T and FVL mutation detection was done in all the subjects. Vegetarianism was found to be significant risk factors for all the pregnancy complications and also when assessed individually. With respect to MTHFR C677T polymorphism, higher frequency of 677T allele was found among controls as compared to cases. 677T allele was found to pose decreased risk for various pregnancy complications on the whole and also individually. On adjusting the diet, regression analysis revealed no risk of mutant allele (T) for various pregnancy complications. FVL homozygous mutants were found to be absent among controls. In conclusion, the present study depicts dietary pattern as one of the most important factors in demonstrating the role of MTHFR C677T in various pregnancy complications and is indicative of a relatively deleterious effect of double dose of FVL in the presently studied population. Additionally, these polymorphisms play an important role in the orchestration of PIH to IUGR and vice versa.

Association of TCF7L2 and ADIPOQ with body mass index, waist-hip ratio, and systolic blood pressure in an endogamous ethnic group of India.

Despite the increasing burden of type 2 diabetes (T2D) and its established association with anthropometric and physiological traits as a risk factor, genetic studies focusing on the association of T2D-related genes with quantitative traits like body mass index (BMI), waist-hip ratio (WHR), and systolic blood pressure (SBP) are only a few for western populations and rare for Indian populations. The present study tested the association of TCF7L2, HHEX, KCNJ11, and ADIPOQ with BMI, SBP, and WHR in men and women of the Aggarwal population of India and found a differential association of TCF7L2 (rs7903146, rs4506565, and rs12256372) and ADIPOQ (rs2241766 and rs1501299) genes with increasing BMI, SBP, and WHR between the two sexes. We conclude that TCF7L2 and ADIPOQ together might play an important role in explaining these traits and to understand the biological and genetic mechanisms underlying T2D, and the role of other T2D genes must also be evaluated with these continuous traits.

Haptoglobin polymorphism among fourteen populations of India.

Haptoglobin (HP) is a serum protein that has the capability of binding the extracorpuscular haemoglobin released during haemolysis. It plays an important role in protection of haemolytic disease by reducing the oxidative and peroxidative potential at free haemoglobin. The present study was aimed to determine the prevalence of HP polymorphism among different Indian populations, anthropologically belonging to diverse ethnicity. The polymorphism was screened among 642 unrelated individuals belonging to 14 population groups of India including both tribal and non-tribal caste groups from different geographical regions of India with distinct linguistic affiliations. An attempt is also made to understand the distribution of HP polymorphism among the studied populations. The result reveals the HP gene to be polymorphic in all the studied populations. Except the two tribal populations (Thotis of Andhra Pradesh and Patelias of Rajasthan) and one caste population (Rajput of Himachal Pradesh), all the studied populations are found to obey the Hardy-Weinberg equilibrium. The significance of the present study is elucidated with the prevalence of high mutant HP*2 allele frequency in India. Selection could be one of the most plausible explanations for this high HP frequency because of its uniformly high occurrence among all the studied populations.

Spectrum of MTHFR gene SNPs C677T and A1298C: a study among 23 population groups of India.

Elevated homocysteine is a risk factor for many complex disorders. The role of methylenetetrahydrofolate reductase (MTHFR) gene in methylation of homocysteine makes it one of the most important candidate genes for these disorders. Considering the heterogeneity in its distribution in world populations, we screened MTHFR C677T and A1298C single nucleotide polymorphisms in a total of 23 Indian caste, tribal and religious population groups from five geographical regions of India and belonging to four major linguistic groups. The frequencies of MTHFR 677T and 1298C alleles were found to be 10.08 and 20.66%, respectively. MTHFR homozygous genotype 677TT was absent in eight population groups and homozygous 1298CC was absent in two population groups. 677T allele was found to be highest among north Indian populations with Indo-European tongue and 1298C was high among Dravidian-speaking tribes of east India and south India. The less common mutant haplotype 677T-1298C was observed among seven population groups and overall the frequency of this haplotype was 0.008, which is similar to that of African populations. cis configuration of 677T and 1298C was 0.94%. However, we could not find any individual with four mutant alleles which supports the earlier observation that presence of more than two mutant alleles may decrease the viability of foetus and possibly be a selective disadvantage in the population.

The genomic similarities with linguistic difference: a study among the Oraon and Munda tribes of the Ranchi district, Jharkhand, India.

AIMS: The present study was conducted on two tribal communities, the Oraon and Munda, inhabiting the Ranchi district of Jharkhand state, India. The study was designed to elucidate genetic similarity, if any, shared between these tribes as they belong to the common Proto-Australoid stock but bear different linguistic affiliations. For this, a total of 98 intravenous blood samples (48 Oraon and 50 Munda) were collected from unrelated individuals of either sex up to first cousins, with their prior informed written consent. The DNA was extracted and studied for a total of 20 autosomal markers, including 7 Alu Indels, 3 DRD2 TaqI sites, 3 ß-globin sites, and 7 restriction site polymorphisms. RESULTS: All the 20 studied molecular markers were found to be polymorphic in both the tribal population groups and showed similarities with respect to allele frequencies, with a low coefficient of gene differentiation (G(ST)) value. Moreover, sharing and distribution patterns of haplotypes of the ß-globin gene cluster suggest that the Oraon and Munda share a common ancestry. However, small differences between them with reference to the linkage disequilibrium (LD) pattern indicate that the Munda might have emerged as a result of admixture between Proto-Australoids and Austro-Asiatic-speaking Mongoloids as supported by the principal co-ordinate analysis, wherein the Munda are closely placed with the Dravidian-speaking Proto-Australoid tribes of India. CONCLUSION: A common genetic substratum (Proto-Australoid stock) of the Oraon and Munda was evident in the present study, although these tribes are distinct linguistically.

A genomic insight into the peopling of Manipur, India.

INTRODUCTION: manipur, one of the northeastern states of India, lies on the ancient silk route and serves as a meeting point between the Southeast Asia and South Asia. AIMS: this study was conducted to understand and estimate the genomic diversity among various population groups of Manipur, with a major goal of getting an insight into the peopling of India. METHODS: seven human-specific Alu insertion/deletion polymorphisms were screened on 366 individuals belonging to eight ethnic groups of Manipur, including both tribal (Aimol, Kabui, Kom, Paite, and Thadou) and nontribal populations (Bamon, Muslims, and Meitei). RESULTS: all the biallelic loci are polymorphic except CD4, which is monomorphic in six out of the eight studied populations. The average heterozygosity values are low (0.309-0.395), with relatively higher average heterozygosity values among Bamons and Muslims than other studied populations, suggesting admixture in these two populations. Lower heterozygosity values of the tribal populations place them closer to the Chinese and Southeast Asian populations, indicating their late arrival in India coupled with geographical isolation. CONCLUSION: this study provides evidence for the genetic heterogeneity of the Manipur populations. It also supports the hypothesis, based on the archeological and linguistic findings, that the northeastern populations of India have a close genetic affinity with the southeastern and East Asian populations. The genetic discontinuity observed between the studied populations and the other non-Northeast Indian populations suggests the role of northeast border as a "barrier" rather than a corridor.

Population structure of Aggarwals of north India as revealed by molecular markers.

Using molecular genetic data on Aggarwals (Vaish/Vysya), an endogamous population group of north India, we provide evidence of its homogeneous unstratified population structure. We found the mean average heterozygosity value of 0.33 for 14 single nucleotide polymorphisms belonging to four genes (TCF7L2-, HHEX-, KCNJ11-, and ADIPOQ-) in the Aggarwal population (sample of 184 individuals) and tried to evaluate the genomic efficiency of endogamy in this population with the help of clan-based stratified analysis. We concluded that the sociocultural identity of the endogamous population groups could act as a robust proxy maker for inferring their homogeneity and population structure in India, which is ideal also for population selection for future genome-wide association studies in the country.

Significance of genome-wide association studies in molecular anthropology.

The successful advent of a genome-wide approach in association studies raises the hopes of human geneticists for solving a genetic maze of complex traits especially the disorders. This approach, which is replete with the application of cutting-edge technology and supported by big science projects (like Human Genome Project; and even more importantly the International HapMap Project) and various important databases (SNP database, CNV database, etc.), has had unprecedented success in rapidly uncovering many of the genetic determinants of complex disorders. The magnitude of this approach in the genetics of classical anthropological variables like height, skin color, eye color, and other genome diversity projects has certainly expanded the horizons of molecular anthropology. Therefore, in this article we have proposed a genome-wide association approach in molecular anthropological studies by providing lessons from the exemplary study of the Wellcome Trust Case Control Consortium. We have also highlighted the importance and uniqueness of Indian population groups in facilitating the design and finding optimum solutions for other genome-wide association-related challenges.