October 04, 2010

Y chromosomes of Vlax Roma

From the paper:
The Gypsies arrived in Europe 900–1100 years ago, when they first appeared in the Balkans. The present-day Gypsy population groups in Europe are the compound product of the early migrations from the Balkans into Europe [1]. The Gypsies came to Hungary from the Balkans in two large migrations. The Carpathian Romanies arrived in the 15th century and the Vlax Romanies came in the 19th century. The Carpathian Gypsies speak Hungarian and the Vlax Romanies speak Hungarian and Romani languages.
Interesting:
A median-joining (MJ) network of haplogroup H1a-M82 has demonstrated the sharing of identical Indian specific Y-chromosomal lineages between all Romani populations including Malaysian Indians as well as the Vlax Romanies (Fig. 2A and B). This common lineage of haplogroup H1a-M82 represents a common descent from a single ancestor providing a strong genetic link to the ancestral geographical origin of the proto-Gypsies [1]. According to Sengupta et al. [24] the age of microsatellite variation within haplogroup H1 in Indian populations is more than 9.7 +/- 4.4 ky. This time was estimated to be 992 years (95%CI 425–3472) in the Romani populations investigated by Gresham et al. [1] suggesting the Indian H1 haplogroup is the ancestral one.
Gresham et al. (pdf) used the genealogical mutation rate. Hence, the discrepancy between the Sengupta et al. age estimates and their own is partly due to the choice of mutation rate. Nonetheless, it's obvious that the Balkan H1 is still 3 times younger than the Indian one, and obviously of South Asian origin. Notice also how the Gresham et al. paper gives a large confidence interval for its estimate, in agreement with my observations about the inadequacy of a limited number of Y-STRs, and Y-STRs in general to couple tightly with historical events.

Nonetheless, if one uses an order-of-magnitude approach, the Gresham et al. estimate is quite compatible with historical knowledge about the arrival of Gypsy founders to the Balkans, just as was the case for Serbian Roma.

The ~1ky estimate for Balkan Gypsy H1 is similar to the ~1ky estimate for the updated J1 Cohen Modal Haplotype. For reasons explained in that post, this is probably an overestimate, and I can envision a scenario according to which the tribal descendants of an H1-man who lived in the 1st millennium AD made their way to Europe at the turn of the millennium, proliferating into the Gypsy communities of today.

Related:

Forensic Science International: Genetics doi:10.1016/j.fsigen.2010.08.017

Paternal genetic history of the Vlax Roma

Andrea Zalán et al.

Romanies constitute the largest minority group belonging to different subgroups in Hungary. Vlax Romanies are one of these Romani subgroups. The Gypsies came to Hungary from the Balkans in two large migrations. The Carpathian Romanies arrived in the 15th century and the Vlax Romanies came in the 19th century. The Carpathian Gypsies speak Hungarian and the Vlax Romanies speak Hungarian and Romani languages.
Only a limited number of genetic studies of Y-chromosomal haplotypes/haplogroups have been done before, moreover most studies did not contain information regarding the investigated Roma populations which subgroups belong to.
In the present study, we analyzed a wide set of Y-chromosomal markers to do comparable studies of the Vlax Roma in eastern Hungarian regions. The results can be compared in the context of previously published data on other Romani groups, Indian and Hungarian reference populations.
Haplogroups H1a-M82 and J2a2-M67 were most common in the investigated population groups. A median-joining network of haplogroup H1a-M82 has demonstrated the sharing of identical Indian specific Y-chromosomal lineages between all Romani populations including Malaysian Indians as well as the Vlax Romanies. This common lineage of haplogroup H1a-M82 represents a common descent from a single ancestor provides a strong genetic link to the ancestral geographical origin of the proto-Gypsies.
The detected haplogroups in the Vlax Romani population groups can be classified into two different Y-chromosomal lineages based on their putative origin. These lineages include ancestral Indian (H1a-M82), present-day Eurasian (J2a2-M67, J2*-M172, E1b1b1a-M78, I1-M253, R1a1-M198 and R1b1-P25) Y-chromosome lineages. Presence of these lineages in the paternal gene pool of the Roma people is illustrative of the Gypsy migration route from India through the Balkan to the Carpathian Basin.

2 comments:

clusteredmaps said...

At K=3 I believe you intended for
blue to represent the Mongoloid cluster.

Unknown said...

Hi,
some linguists have come up with the theory that the Roma do not stem from a single population but from different regions and casts in central, north-eastern and partly north-western India. Do the findings contradict such a hypothesis in any way?