Molecular genetic perspectives on the Indian social structure

Reddy, B. Mohan; Tripathy, Vikal; Kumar, Vikrant; Nirmala, A.

doi:10.1002/ajhb.20983

Cited by 9 publications

(7 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Tibeto-Burman and Austro-Asiatic languages have a more restricted geographic distribution, that is, the Northeast and Central India (Cordaux et al. 2004; Reddy et al. 2010; Chaubey et al.…”

Section: Introductionmentioning

confidence: 99%

A Genome-Wide Association Study of Skin and Iris Pigmentation among Individuals of South Asian Ancestry

Jonnalagadda

Faizan

Ozarkar

et al. 2019

Genome Biology and Evolution

View full text Add to dashboard Cite

South Asia has a complex history of migrations and is characterized by substantial pigmentary and genetic diversity. For this reason, it is an ideal region to study the genetic architecture of normal pigmentation variation. Here, we present a meta-analysis of two genome-wide association studies (GWASs) of skin pigmentation using skin reflectance (M-index) as a quantitative phenotype. The meta-analysis includes a sample of individuals of South Asian descent living in Canada ( N = 348), and a sample of individuals from two caste and four tribal groups from West Maharashtra, India ( N = 480). We also present the first GWAS of iris color in South Asian populations. This GWAS was based on quantitative measures of iris color obtained from high-resolution iris pictures. We identified genome-wide significant associations of variants within the well-known gene SLC24A5 , including the nonsynonymous rs1426654 polymorphism, with both skin pigmentation and iris color, highlighting the pleiotropic effects of this gene on pigmentation. Variants in the HERC2 gene (e.g., rs12913832) were also associated with iris color and iris heterochromia. Our study emphasizes the usefulness of quantitative methods to study iris color variation. We also identified novel genome-wide significant associations with skin pigmentation and iris color, but we could not replicate these associations due to the lack of independent samples. It will be critical to expand the number of studies in South Asian populations in order to better understand the genetic variation driving the diversity of skin pigmentation and iris color observed in this region.

show abstract

Section: Introductionmentioning

confidence: 99%

A Genome-Wide Association Study of Skin and Iris Pigmentation among Individuals of South Asian Ancestry

Jonnalagadda

Faizan

Ozarkar

et al. 2019

Genome Biology and Evolution

View full text Add to dashboard Cite

show abstract

“…Tribal populations are considered to be the indigenous populations of India and constitute approximately 8.63% of the total population 2 . The non-tribal populations consist of religious communities outside the caste system, and hierarchically arranged, endogamous social groups known as castes 3 . This fundamental division of the Indian population into castes, tribes and religious groups has resulted in a large number of effective populations or endogamous groups 1,3 .…”

mentioning

confidence: 99%

Novel insights on demographic history of tribal and caste groups from West Maharashtra (India) using genome-wide data

Debortoli

Abbatangelo

Ceballos

et al. 2020

Sci Rep

View full text Add to dashboard Cite

the South Asian subcontinent is characterized by a complex history of human migrations and population interactions. In this study, we used genome-wide data to provide novel insights on the demographic history and population relationships of six indo-european populations from the indian State of West Maharashtra. the samples correspond to two castes (Deshastha Brahmins and Kunbi Marathas) and four tribal groups (Kokana, Warli, Bhil and Pawara). We show that tribal groups have had much smaller effective population sizes than castes, and that genetic drift has had a higher impact in tribal populations. We also show clear affinities between the Bhil and Pawara tribes, and to a lesser extent, between the Warli and Kokana tribes. Our comparisons with available modern and ancient DnA datasets from South Asia indicate that the Brahmin caste has higher Ancient iranian and Steppe pastoralist contributions than the Kunbi Marathas caste. Additionally, in contrast to the two castes, tribal groups have very high Ancient Ancestral South indian (AASi) contributions. indo-european tribal groups tend to have higher Steppe contributions than Dravidian tribal groups, providing further support for the hypothesis that Steppe pastoralists were the source of Indo-European languages in South Asia, as well as europe.

show abstract

“…The six study populations belonged to two distinct social groups, i.e. castes and tribes, which forms a unique feature of the Indian population structure resulting into a large number of effective populations maintained due to endogamous matings (Reddy et al, 2010). Pair-wise F ST statistics were run to evaluate the extent of population differentiation at this locus.…”

Section: Inter-population Variationmentioning

confidence: 99%

MC1R diversity and its role in skin pigmentation variation in West Maharashtra, India

Jonnalagadda

Bharti

Kasibhatla

et al. 2022

American J Hum Biol

View full text Add to dashboard Cite

Objectives MC1R polymorphisms have been reported to be under a selective constraint in populations inhabiting high UVR regions such as Africans; however, these patterns are not consistent. Here we analyze the MC1R gene in West Maharashtra, India to see if sequence diversity corresponds to their diverse pigmentary profiles and if MC1R is constrained in dark skinned tribal as compared to lighter skinned caste populations. Methods A 2648 bp region of this gene was sequenced in 102 individuals and the data was compared for π, ϴ diversity indices. Tajima's D was assessed for signatures of purifying selection and MC1R variants were associated with MI measures using the additive, dominant, and recessive models. Pairwise FST was tested among study populations and between study populations and 1000 Genomes regional samples. Results MC1R diversity was not uniquely patterned among castes and tribes. Non‐synonymous variants rs2228479A, rs1805007_T, and rs885479_A showed low variability in these populations. Selection tests did not indicate any constraint on MC1R and pairwise FST were also low among the study populations (−0.0163 to 0.06112). The SNP rs3212359 was significantly associated with MI measures when tested using different association models. Conclusions We do not find evidence of a selective constraint on MC1R. The presence of a large number of unique haplotypes and low FST values at this locus suggests that MC1R polymorphisms may not be influencing pigmentation variation among castes and tribes in this region. Observed associations between rs3212359 and MI measures need to be validated through studies on larger samples and in‐vitro functional studies.

show abstract

Molecular genetic perspectives on the Indian social structure

Cited by 9 publications

References 27 publications

A Genome-Wide Association Study of Skin and Iris Pigmentation among Individuals of South Asian Ancestry

A Genome-Wide Association Study of Skin and Iris Pigmentation among Individuals of South Asian Ancestry

Novel insights on demographic history of tribal and caste groups from West Maharashtra (India) using genome-wide data

MC1R diversity and its role in skin pigmentation variation in West Maharashtra, India

Contact Info

Product

Resources

About