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Euclides
Friday, March 12th, 2004, 01:52 PM
Contrasting patterns of Y chromosome variation in Ashkenazi Jewish and host non-Jewish European populations
Doron M. Behar1, Daniel Garrigan2, Matthew E. Kaplan2, Zahra Mobasher2, Dror Rosengarten1, Tatiana M. Karafet2, Lluis Quintana-Murci3, Harry Ostrer4, Karl Skorecki1, 5 and Michael F. Hammer2

(1) Bruce Rappaport Faculty of Medicine and Research Institute, Technion and Rambam Medical Center, Haifa, Israel
(2) Division of Biotechnology, University of Arizona, Tucson, Arizona, USA
(3) CNRS URA1961, Institut Pasteur, Paris, France
(4) Human Genetics Program, New York University School of Medicine, New York, USA
(5) Department of Nephrology and Molecular Medicine, Technion and Rambam Medical Center, POB 9602, 31096 Haifa, Israel




Abstract

The molecular basis of more than 25 genetic diseases has been described in Ashkenazi Jewish populations. Most of these diseases are characterized by one or two major founder mutations that are present in the Ashkenazi population at elevated frequencies. One explanation for this preponderance of recessive diseases is accentuated genetic drift resulting from a series of dispersals to and within Europe, endogamy, and/or recent rapid population growth. However, a clear picture of the manner in which neutral genetic variation has been affected by such a demographic history has not yet emerged. We have examined a set of 32 binary markers (single nucleotide polymorphisms; SNPs) and 10 microsatellites on the non-recombining portion of the Y chromosome (NRY) to investigate the ways in which patterns of variation differ between Ashkenazi Jewish and their non-Jewish host populations in Europe. This set of SNPs defines a total of 20 NRY haplogroups in these populations, at least four of which are likely to have been part of the ancestral Ashkenazi gene pool in the Near East, and at least three of which may have introgressed to some degree into Ashkenazi populations after their dispersal to Europe. It is striking that whereas Ashkenazi populations are genetically more diverse at both the SNP and STR level compared with their European non-Jewish counterparts, they have greatly reduced within-haplogroup STR variability, especially in those founder haplogroups that migrated from the Near East. This contrasting pattern of diversity in Ashkenazi populations is evidence for a reduction in male effective population size, possibly resulting from a series of founder events and high rates of endogamy within Europe. This reduced effective population size may explain the high incidence of founder disease mutations despite overall high levels of NRY diversity.

Vetinari
Friday, March 12th, 2004, 06:41 PM
Contrasting patterns of Y chromosome variation in Ashkenazi Jewish and host non-Jewish European populations
Doron M. Behar1, Daniel Garrigan2, Matthew E. Kaplan2, Zahra Mobasher2, Dror Rosengarten1, Tatiana M. Karafet2, Lluis Quintana-Murci3, Harry Ostrer4, Karl Skorecki1, 5 and Michael F. Hammer2


I think that you may have attached the wrong file. When I clicked on your link the report that came up was titled "Modulation of penetrance by the wild-type allele in dominantly inherited erythropoietic protoporphyria and acute hepatic porphyrias".

Euclides
Monday, March 15th, 2004, 06:09 PM
I think that you may have attached the wrong file. When I clicked on your link the report that came up was titled "Modulation of penetrance by the wild-type allele in dominantly inherited erythropoietic protoporphyria and acute hepatic porphyrias".


Sorry for this...but in other hand I am happy because your interests in genetics. I am attaching the correct article.

Vetinari
Monday, March 15th, 2004, 07:16 PM
Sorry for this...but in other hand I am happy because your interests in genetics. I am attaching the correct article.

Thanks for the file! Do you also have a copy of the pdf version of this research?

Vetinari
Monday, November 8th, 2004, 03:33 PM
Recent genetic studies, based on Y chromosome polymorphic markers, showed that Ashkenazi Jews are more closely related to other Jewish and Middle Eastern groups than to their host populations in Europe. However, Ashkenazim have an elevated frequency of R-M17, the dominant Y chromosome haplogroup in Eastern Europeans, suggesting possible gene flow. In the present study of 495 Y chromosomes of Ashkenazim, 57 (11.5%) were found to belong to R-M17. Detailed analyses of haplotype structure, diversity and geographic distribution suggest a founder effect for this haplogroup, introduced at an early stage into the evolving Ashkenazi community in Europe. R-M17 chromosomes in Ashkenazim may represent vestiges of the mysterious Khazars.

http://www.gnxp.com/MT2/khazar.pdf