Commentary has a long piece, Jews and Their DNA, which covers the recent findings coming out of genetics in regards to the "Who is a Jew" question. It's a fair summary of the field, though I would note that the author relied heavily on uniparental lineages passed purely through males and females, and that autosomal studies which look at total genome content are now coming to the fore and fleshing out the picture. I suspect that the main result that will come out of these findings is that many, many, groups are going to be unhappy. Some will find that Jewish ancestry is admixed and that they are not a pure people apart. Others will be rather annoyed that to some extent Jewishness does map onto particular patterns of genetic variation which make Jews distinct from local non-Jewish populations. In other words, Judaism is not purely a cultural construct. Extremely religious Jews who are wedded to the matrilineal formula for Jewish identity will likely dismiss the convincing data for exogenous introgression over the generations through female mediated admixture. As I have noted before, even a 1% exogamy rate over 2,000 years builds up.
Judaism is a pure cultural construct, whether or not Jews are genetically distinct. During the Nazi era there were 100% genetically-Jewish Germans whose families had not been religious or cultural Jews for several generations; likewise in Spain after the expulsion of the Jews. (Many or most convert families did intermarry eventually, but there was no rule that they had to.)
The majority of Jews I've known of eastern European descent (and I've known a lot in my life) have blue eyes. That suggests something other than pure Middle Eastern descent.
What we are finding is the majority of the genetic distinction of Modern Jews derives from completely outside the middle East from large groups of genetically coherent non Levantine people adopting Judaism after the diaspora.
If anything the extant non Jewish populations in Eastern Med and Middle East are much more decedents of the Biblical age Jews than the current populations identifying ourselves as such.
What we are finding is the majority of the genetic distinction of Modern Jews derives from completely outside the middle East from large groups of genetically coherent non Levantine people adopting Judaism after the diaspora.
this is debatable. that's because the admixture is probably in the middle range (e.g., 60-40 either way). so you could technically be right, but probably not.
If anything the extant non Jewish populations in Eastern Med and Middle East are much more decedents of the Biblical age Jews than the current populations identifying ourselves as such.
i think this is a gross oversimplification, though not totally unfair.