Almost Half Ashkenazi Jews Descend From 4 Women

According to Wikipedia, Ashkenazi Jews make up almost 80% of the entire world's jewry.   Now a genetic study indicates that 40% of these descend from just four women.   Those women apparently lived somewhere in Europe within the last 2,000 years, but not necessarily in the same place or even the same century.   Each woman left a genetic signature that shows up in their descendants today according to a report published online by the American Journal of Human Genetics.   Together, their four signatures appear in about 40 percent of Ashkenazi Jews, while being virtually absent in non-Jews and found only rarely in Jews of non-Ashkenazi origin. The study used mitochondrial DNA from more than 11,000 samples representing 67 populations.   mitochondrial DNA is passed only from mother to daughter.