It wasn’t just Eve? From Study: Most Ashkenazi Jews From Four Women:
Some 3.5 million of today’s Ashkenazi Jews — about 40 percent of the total Ashkenazi population — are descended from just four women, a genetic study indicates.
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Ashkenazi Jews are a group with mainly central and eastern European ancestry. Ultimately, though, they can be traced back to Jews who migrated from Israel to Italy in the first and second centuries, Behar said. Eventually this group moved to Eastern Europe in the 12th and 13th centuries and expanded greatly, reaching about 10 million just before World War II, he said.The study involved mitochondrial DNA, called mtDNA, which is passed only through the mother. A woman can pass her mtDNA to grandchildren only by having daughters. So mtDNA is “the perfect tool to trace maternal lineages,” Behar said Thursday in a telephone interview.
His study involved analyzing mtDNA from more than 11,000 samples representing 67 populations.