Do you remember learning about genes and DNA, about inherited traits and about Gregor Mendel’s pea plants? It has long been known and accepted as a scientific fact that each person’s DNA makes them, on a physical level, who they are, and unique from everyone else. In recent decades, as genetic science advances and becomes more accessible to the general populace, droves of people are experimenting with genetic testing to understand who they are – at least from a heritage point of view.

As this coming Friday, April 25th commemorates the successful completion of the Human Genome Project in 2003 and the discovery of DNA’s double helix in 1953, Jewish Treats presents a brief overview of the concept of Jewish DNA and its implications for the Jewish people.

As unlocking ethnic heritage became possible via genetics, it is not surprising that researchers chose to study the Jewish people. Here researchers had a large, multi-national group of people claiming common ancestry. Even more interesting is that among Jews, there was a sub-group claiming to be kohanim (Cohen, of the priestly descent) who are, according to the Torah, all descendants of Aaron.

Studies of kohanim showed that a significant percentage of those claiming to be part of the priestly caste, whether Ashkenazi, Sephardi or other, shared a unique haplotype on the Y chromosome, consistently transmitted from father to son. While studies of the Jewish population in general were not quite as specific, studies have recognized distinct links that even cross continental borders.

What does all this mean for the 21st century Jewish community? The Jewish people have never been 100% homogeneous. Even in Biblical days, the Jewish people accepted converts (Jethro, Ruth), and in the many millennia since then there have been Jews of every race and ethnicity. Since, according to traditional Jewish law, a person is Jewish if born of a Jewish mother (unless one converts), questions have been raised as to whether DNA can be used to establish Jewish identity. Jewish Treats humbly leaves that question to real experts in Jewish law.

Copyright © 2025 NJOP. All rights reserved.