IE & genes

I just read this in Palanth-I. Comments?

R. Casalotti, L. Simoni, M. Belledi, G. Barbujani 1999 "Y-chromosome polymorphisms and the origins of the European gene pool" Proc.R.Soc.Lond.B 266 Issue 1432 : 1959-1965

Gradients of allele frequencies have long been considered the main genetic characteristic of the European population, but mtDNA diversity seems to be distributed differently. One Alu insertion (YAP), 5 tetranucleotide (DYS19, DYS389B, DYS390, DYS391 and DYS393) and 1 trinucleotide (DYS392) microsatellite loci of the Y chromosome were analysed for geographical patterns in 59 European populations. Spatial correlograms showed clines for most markers, which paralleled the gradients previously observed for two RFLP polymorphisms. Effective separation times between populations were estimated from genetic distances at microsatellite loci. Even after correcting for the possible effects of continuous local gene flow, the most distant IE-speaking populations seem to have separated no more than 7000 ya. The clinal patterns and the estimated, recent separation times between populations jointly suggest that Y-chromosome diversity in Europe largely reflects a directional demic expansion, which is unlikely to have occurred before the Neolithic period. Our comparison of craniofacial form from the Middle East westwards to the British Isles and Scandinavia from the Neolithic on suggests that the Neolithic did involve the establishment of colonies or limited size in areas favorable to primitive agriculture and that these were minority beach heads in Mesolithic Europe. Ultimately the indigenous people converted to farming and absorbed those initial Neolithic colonies which were not large enough to have any visible impact on the continuing gene pool. The linguistic situation was more likely to have been shaped by the Bronze Age extensions of economic and political control over those indigenous populations. In effect, there was minimal population movement, and the picture of diversity in IE languages was created by the survival of locally differing non-IE elements modifying the imposed IE speech patterns. What had originally been great non-IE linguistic diversity -- comparable to that in New Guinea today -- was brought into a kind of convergence by the imposition of an IE pattern. So far, this kind of expectation has never been used to test the genetic data. The archaeological picture providing independent support for these expectations has been presented by Marek Zvelebil (ed.) 1986. Hunters in Transition: Mesolithic Societies of Temperate Eurasia and Their Transition To Farming. Cambridge UP (C. L. Brace)

Marc