Thus, the AJ population shows evidence of past founding events; however, admixture and selection have also strongly influenced its current genetic makeup." Excerpts from page 16222: "The Ashkenazi Jewish (AJ) population has long been viewed as a genetic isolate, kept separate from its European neighbors by religious and cultural practices of endogamy (1).[...] Y-chromosome studies also indicate only a low amount of admixture with neighboring Europeans (8-10)."Abraham's Children in the Genome Era: Major Jewish Diaspora Populations Comprise Distinct Genetic Clusters with Shared Middle Eastern Ancestry." The American Journal of Human Genetics 86:6 (June 3, 2010): pages 850-859.Abstract: "For more than a century, Jews and non-Jews alike have tried to define the relatedness of contemporary Jewish people.
Two major groups were identified by principal component, phylogenetic, and identity by descent (IBD) analysis: Middle Eastern Jews and European/Syrian Jews.Thus, this study demonstrates that European/Syrian and Middle Eastern Jews represent a series of geographical isolates or clusters woven together by shared IBD genetic threads." "The genetic, cultural and religious traditions of contemporary Jewish people originated in the Middle East over three thousand years ago.Since that time, Jewish communities have migrated from the Middle East into Europe, North Africa and across the world. This study shows that although Jewish people experienced genetic mixing with surrounding populations, they retained a genetic coherence along with a religious one.Previous genetic studies of blood group and serum markers suggested that Jewish groups had Middle Eastern origin with greater genetic similarity between paired Jewish populations.However, these and successor studies of monoallelic Y chromosomal and mitochondrial genetic markers did not resolve the issues of within and between-group Jewish genetic identity.