The Indian origin of paternal haplogroup R1a1* substantiates the autochthonous origin of Brahmins and the caste system

Abstract

Many major rival models of the origin of the Hindu caste system co-exist despite extensive studies, each with associated genetic evidences. One of the major factors that has still kept the origin of the Indian caste system obscure is the unresolved question of the origin of Y-haplogroup R1a1*, at times associated with a male-mediated major genetic influx from Central Asia or Eurasia, which has contributed to the higher castes in India. Y-haplogroup R1a1* has a widespread distribution and high frequency across Eurasia, Central Asia and the Indian subcontinent, with scanty reports of its ancestral (R*, R1* and R1a*) and derived lineages (R1a1a, R1a1b and R1a1c). To resolve these issues, we screened 621 Y-chromosomes (of Brahmins occupying the upper-most caste position and schedule castes/tribals occupying the lower-most positions) with 55 Y-chromosomal binary markers and seven Y-microsatellite markers and compiled an extensive dataset of 2809 Y-chromosomes (681 Brahmins, and 2128 tribals and schedule castes) for conclusions. A peculiar observation of the highest frequency (up to 72.22%) of Yhaplogroup R1a1* in Brahmins hinted at its presence as a founder lineage for this caste group. Further, observation of R1a1* in different tribal population groups, existence of Y-haplogroup R1a* in ancestors and extended phylogenetic analyses of the pooled dataset of 530 Indians, 224 Pakistanis and 276 Central Asians and Eurasians bearing the R1a1* haplogroup supported the autochthonous origin of R1a1 lineage in India and a tribal link to Indian Brahmins. However, it is important to discover novel Y-chromosomal binary marker(s) for a higher resolution of R1a1* and confirm the present conclusions.

Brief communication: Allelic and haplotypic structure at the DRD2 locus among five North Indian caste populations

“…The emergence of caste system in India has been attributed to many different causes. For example, some suggest it was initiated by the Aryan invasion (Poliakov, 1974;Renfrew 1989a,b); that it evolved from a common genetic heritage along with tribes (Kivisild et al, 2003); that it originated independent of tribes (Cordaux et al, 2004) or that it has existed since time immemorial (Karve, 1961;Sharma et al, 2009). Some authors also put forth the theory of tribe caste continuum Thanseem et al, 2006), i.e., the evolution of castes from preexisting tribal groups.…”

“…Indian Human Genome diversity studies using mitochondrial (Bamshad et al, 2001;Kivisild et al, 2003;Quintana-Murci et al, 2004), Y chromosomal (Sengupta et al, 2006;Sharma et al, 2009), and autosomal DNA markers (Watkins et al, 2005;Indian Genome Variation Consortium, 2008;Reich et al, 2009) have tried to address the human settling of India with special reference to the castes and tribes of India. Linguistic studies also illustrate the group divisions within India: Indo-European languages are spoken by all caste populations except those of South India.…”

Haplogroup R1a, Its Subclades and Branches in Europe During the Last 9,000 Years

“…R1a was identified in excavated DNA in Germany with the dating of 4600 ybp (Haak et al, 2008), in Siberia, with the dating of 3800 -3400 ybp (Keyser et al, 2009), in Tarim Basin, Xinjiang, China, with the dating of ~4000 ybp (Li et al, 2010). Its distribution was described in various parts of Eurasia (e.g., Wells et al, 2001;Behar et al, 2003;Cinnioglu et al, 2004;Kharkov et al, 2004;Sengupta et al, 2006;Balanovsky et al, 2008;Sharma et al, 2009;Underhill et al, 2009;Abu-Amero et al, 2009). However, only in the last few years, thank mainly to efforts of Dr. Peter Underhill's laboratory at Stanford University, Dr. Thomas Krahn of Family Tree DNA's Genomics Research Center, and researchers of 1000 Genomes Project, many new SNPs in haplogroup R1a have been discovered; as indicated by beginning letters M, L, and Z, respectively, in the SNPs below.…”

Inferring population structure and relationship using minimal independent evolutionary markers in Y-chromosome: a hybrid approach of recursive feature selection for hierarchical clustering

“…Later, analysis was repeated in a set of 79 populations (10 890 samples from diverse geographical regions, e.g. South Asia including major geographic regions of India (49) and Pakistan, Caucasus, Near/Middle East, Central Asia, South-East Asia, Russia, Europe and USA) and 105 populations (12 835 samples from diverse regions of world) (Supplementary Table S4) to confirm the results obtained in the initial analysis.…”

“…al. , (49) and Pakistan); Caucasus; Near/Middle East (Iran, Georgia and Turkey); Central Asian (Gulf Countries and Iraq); South East Asian including Mongolians and others; European; USA and African populations using principal component analysis (PCA), based on 15, 25 and 32 common haplogroups (variables) for a set of 50, 79 and 105 populations.…”