November 29, 2012

Pinpointing Roma origins: Out of Northwestern India

Interestingly, besides H-M82, there has been recent evidence that R-Z93 might also represent a second founder haplogroup of the European Roma populations; it will be interesting to study it in the future in order to confirm the scenario presented in this new paper.

From the paper:
This first genetic evidence of this nature allows us to develop a more detailed picture of the paternal genetic history of European Roma, revealing that the ancestors of present scheduled tribes and scheduled caste populations of northern India, traditionally referred to collectively as the Ḍoma, are the likely ancestral populations of modern European Roma. Our findings corroborate the hypothesized cognacy of the terms Rroma and Ḍoma and resolve the controversy about the Gangetic plain and the Punjab in favour of the northwestern portion of the diffuse widespread range of the Ḍoma ancestral population of northern India.
A paper about Roma origins based on autosomal DNA is also apparently in the works, so it will be interesting to see how it might tie in with the Y-chromosome evidence.

PLoS ONE 7(11): e48477. doi:10.1371/journal.pone.0048477

The Phylogeography of Y-Chromosome Haplogroup H1a1a-M82 Reveals the Likely Indian Origin of the European Romani Populations

Niraj Rai et al.

Linguistic and genetic studies on Roma populations inhabited in Europe have unequivocally traced these populations to the Indian subcontinent. However, the exact parental population group and time of the out-of-India dispersal have remained disputed. In the absence of archaeological records and with only scanty historical documentation of the Roma, comparative linguistic studies were the first to identify their Indian origin. Recently, molecular studies on the basis of disease-causing mutations and haploid DNA markers (i.e. mtDNA and Y-chromosome) supported the linguistic view. The presence of Indian-specific Y-chromosome haplogroup H1a1a-M82 and mtDNA haplogroups M5a1, M18 and M35b among Roma has corroborated that their South Asian origins and later admixture with Near Eastern and European populations. However, previous studies have left unanswered questions about the exact parental population groups in South Asia. Here we present a detailed phylogeographical study of Y-chromosomal haplogroup H1a1a-M82 in a data set of more than 10,000 global samples to discern a more precise ancestral source of European Romani populations. The phylogeographical patterns and diversity estimates indicate an early origin of this haplogroup in the Indian subcontinent and its further expansion to other regions. Tellingly, the short tandem repeat (STR) based network of H1a1a-M82 lineages displayed the closest connection of Romani haplotypes with the traditional scheduled caste and scheduled tribe population groups of northwestern India.


1 comment:

genefan said...

It seems there is another haplotype and SNP specific to Roma in Europe and it is I1-P259.
R1a is not common for all European Roma groups, for example Bulgarian and Macedonian Roma are extremely low on R1a and R1b. Z93 is also very common in Asia and present in Europe.
However P259 was found only in literature, from more than 2000 taking the I1 Deep Clade test on FamilyTreeDNa all are negative.
While paying attention to "Ancestral modal Y-STR haplotype shared among Romani and South Indian populations", it mentioned:

The predominantly European haplogroup I-M258, on the other hand, which has two foci of frequencies in northern Europe around Scandinavia (I1) and in the Balkan Peninsula (I2) (Rootsi et al., 2004), supports genetic admixture with host populations following their arrival in the Balkans. It is interesting to note that the I1c-P259 sub-clade, which comprises all "I" chromosomes in the Bogojevo population and 4.5% of patrilineages in the Roma from Belgrade, is absent from the general population of Serbia (Regueiro et al., 2012). In addition, the most common I1c-P259 16 loci-haplotype in our Roma collections (DYS19*14, DYS385*14-14, DYS389I*12, DYS389II*28, DYS390*22, DYS391*10, DYS392*11, DYS393*13, DYS437*16, DYS438*10, DYS439*12, DYS448*20, DYS456*14, DYS458*15, DYS635*22, GATA H4*20) is also the most frequently observed Y-STR profile among the Romani from Portugal and Bulgaria.