Originally Posted by SoCal2NYC
I know it's been brought up before in some huge thread; but, why is it that Jews feel their faith can be used for their nationality/ancestry/lineage?
I guess you didn't find the previous explanations satisfactory?
Science would tell us that Judaism is more than just a religious faith. My previous post on this thread addresses just that. Although my family is from Germany, Austria-Hungary, Prussia and Poland, my y-chromosome haplogroup is rare in those areas. The notable exception is among Jews. On the other hand, my haplogroup is the same as many Arabs (60-80% of Bedouin Arabs) and Samaritans (>80%). This would indicate that I share a liniage with other Jews and Semitic peoples rather than Germanic people.
There are also various genetic disorders common in Jews that are not shared with other "Germans" and "Poles". Some of these include Tay-Sacs disease. 1:30 Ashkenazi Jews are carriers as compared to 1:300 of the general European population; if you are a carrier of Tay-Sacs, there is probably a "Jew in the woodpile". Askenazi Jews also have a very high incidence of BRCA mutations that predispose to breast/ovarian cancer. Being Jewish is also a risk factor for Crohn's disease. Part of taking a family history, for medical reasons, includes listing Jewish decent; I don't think physicians are concerned with the patient's "faith".
Certainly both culture and faith are part of being Jewish and not every Jew is of Jewish decent. Until very recent times, conversion to Judaism was rare, but it is much more common now. In generations to come, this may have an impact on genotype and disease risk factors. This will not be seen in our lifetimes. As humans have become more mobile, intermarriage between all ethnic groups and nationalities have increased. One day we may all be homogeneous, but that day has not yet arrived.