Where did the Jews originate? I had always heard Mesopotamia (modern day Iraq), but just read a paper that showed over 80% of Ashkenazim mtDNA can be traced back to Italy. Anyone have any more conclusive info?
MtDNA shows the maternal line, through mitochondrial DNA. When this is studied there are usually some connections to the Middle East, but mainly Europe.
Studying Y-chromosomes, passing on through the father, shows connections usually in Cyprus, the Levant, and other parts of the Middle East. The studies I've seen suggest that Jews have a strong paternal lineage and common ancestor from the Middle East, and a group of 350-400 Middle Eastern Jews arrived in Europe 2,000-2,500 years ago and intermarried. That's what I've been able to gather from some of the genetic studies I've seen.