November 03, 2006

Y chromosomes of Czech Republic

From the paper:
The position of Czech samples in the genetic landscape of central Europe emerges in Correspondence Analysis (Fig. 2). In the first dimension the Czech samples are clustered and positioned in between the Polish and German samples. In fact Hg’s R1a and N3-Tat (more frequent in Poland) have the largest negative loadings on this dimension, whereas Hg’s K*-M9 and J2*-M172 (more frequent in Germany and Italy) have the largest positive ones. The second dimension is mainly contributed by Hg’s I-M170, E3b1-M78, and K*-M9 (negative loadings) vs. Hg P-DYS257*(xR1a). Thus, the position of the three Balkan populations in Figure 2 is in line with the focal distribution of Hg’s I and E3b1 in this area (Cruciani et al., 2004; Pericic et al., 2005).

These seem to agree with my observations regarding a recent study on Germans and Poles:
We see that Poles are differentiated by Germans on the basis of R1a1 and N3 (Finno-Ugrian admixture). The differentiation on the basis of I subgroups is not evident, because no downstream markers for this haplogroup were examined in this study.

Also of particular interest is that of the two Neolithic haplogroups, J2 is associated with Germans, whereas DE* is apparently not. So, this may hint at different patterns of arrival of the two haplogroups in this part of the world. This would agree with some recent results from Balkan Slavic populations, that typically found a higher-percentage of YAP (DE) lineages than J2 ones.
as well as the observational evidence.

American Journal of Physical Anthropology
(online early)

Y-chromosomal variation in the Czech Republic

F. Luca et al.


To analyze the contribution of the Czech population to the Y-chromosome diversity landscape of Europe and to reconstruct past demographic events, we typed 257 males from five locations for 21 UEPs. Moreover, 141 carriers of the three most common haplogroups were typed for 10 microsatellites and coalescent analyses applied. Sixteen Hg's characterized by derived alleles were identified, the most common being R1a-SRY10831 and P-DYS257*(xR1a). The pool of haplogroups within I-M170 represented the third most common clade. Overall, the degree of population structure was low. The ages for Hg I-M170, P-DYS257*(xR1a), and R1a-SRY10831 ap peared to be comparable and compatible with their presence during or soon after the LGM. A signal of population growth beginning in the first millennium B.C. was detected. Its similarity among the three most common Hg's indicated that growth was characteristic for a gene pool that already contained all of them. The Czech population appears to be influenced, to a very moderate extent, by genetic inputs from outside Europe in the post-Neolithic and historical times. Population growth postdated the archaeologically documented introduction of Neolithic technology and the estimated central value coincides with a period of repeated changes driven by the development of metal technologies and the associated social and trade organization.


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