Human Y chromosomes and the origins of modern European populations
thesisposted on 15.12.2014, 10:38 by Zoë H. Rosser
Three different studies examining Y-chromosomal diversity have been undertaken: a large continent-wide study examining the distribution of biallelic haplogroup diversity within 48 European and circum-European populations; a micro-geographic study examining the haplogroup distribution and diversity within a linguistic isolate of the Italian Alps; and finally, a global study of a single lineage, employing biallelic and multiallelic markers, to try to explain the unusual global distribution of this lineage.;Within the European study, five haplogroups showed significant clinal patterns. Two major continent-wide clines are consistent with the migration of farmers from the Near East. Statistical analyses confirm that populations are related primarily on the basis of geography rather than language. The second study shows that Ladin-speakers have low haplography diversity when compared to neighbouring populations however, a high level of internal diversity was observed using the multiallelic markers. Minisatellite MSY1 examination shows unique alleles within Ladin valleys which suggests either in situ differentiation of an isolated population, or a small, already diverse founding population. Within the final study additional biallelic markers were incorporated using a new typing methodology, enabling the further sub-division of the YAP branch, and some new haplogroups showed population specificity. Increasing the number of microsatellite loci from seven to seventeen allowed improved discrimination within the haplogroups. The dating of mutations enabled historical events to be proposed to explain the unusual geographical distribution of this lineage.