Berlusconi and Netanyahu

Genetic research on the ancestry of Jewish populations tends to get politicized because of the sneaking suspicion that the average Palestinian may be more closely related to the Hebrews of 70 AD than is, say, Bibi Netanyahu.

Here's a new NYT article that validates what always seemed likely just from looking at European Jews: they're part-European.

Genes Suggest European Women at Root of Ashkenazi Family Tree 

By NICHOLAS WADE

Over the last 15 years geneticists have identified links between the world’s Jewish communities that point to a common ancestry as well as a common religion. Still, the origin of one of the most important Jewish populations, the Ashkenazim of Central and Eastern Europe, has remained a mystery.

A new genetic analysis has now filled in another piece of the origins puzzle, pointing to European women as the principal female founders, and to the Jewish community of the early Roman empire as the possible source of the Ashkenazi ancestors. 

The finding establishes that the women who founded the Ashkenazi Jewish community of Europe were not from the Near East, as previously supposed, and reinforces the idea that many Jewish communities outside Israel were founded by single men who married and converted local women. 

The study, published Tuesday in the journal Nature Communications, is based on a genetic analysis of maternal lineages. A team led by Martin B. Richards of the University of Huddersfield in England took a fresh look at Ashkenazi lineages by decoding the entire mitochondrial genomes of people from Europe and the Near East. 

Earlier DNA studies showed that Jewish communities around the world had been founded by men whose Y chromosomes bore DNA patterns typically found in the Near East. But there was a surprise when geneticists turned to examine the women founders by analyzing mitochondrial DNA, a genetic element that is separate from the main human genome and inherited just through the female line. 

... With the entire mitochondrial genome in hand, Dr. Richards could draw up family trees with a much finer resolution than before. His trees show that the four major Ashkenazi [maternal-line] lineages in fact form clusters within descent lines that were established in Europe some 10,000 to 20,000 years ago. The same is true of most of the minor lineages. 

“Thus the great majority of Ashkenazi maternal lineages were not brought from the Levant, as commonly supposed,” Dr. Richards and colleagues conclude in their paper. Overall, at least 80 percent of Ashkenazi maternal ancestry comes from women indigenous to Europe, and 8 percent from the Near East, with the rest uncertain, the researchers estimate. 

Dr. Richards estimates that the four major lineages became incorporated into the Ashkenazi community at least 2,000 years ago. A large Jewish community flourished in Rome at this time and included many converts. This community could have been the source of both the Ashkenazim of Europe and the Sephardim of Spain and Portugal, given that the two groups have considerable genetic commonality, Dr. Richards said.