I had a DNA test done and the results say that my DNA is group with Sephardic Jews. My last name is Steen and I have always heard that we were of Dutch ancestry and I do genealogy and have not found anything stating that anyone was Jewish. I must admit that within myself I always found common ground with people that are Jewish and felt that I may be.
Does having Jewish blood, as indicated in a DNA test, make one Jewish, or is Jewish status defined only based on traditional standards?
Based on Jewish law, a person's Jewish status (for a non-convert) is determined through matrilineal descent. This means that one is only Jewish from birth if their mother was Jewish. And their mother was only Jewish if their mother was Jewish.
Based on this, a person can have seven out of eight great-grandparents who are Jewish, and still not be Jewish from birth (in the case where the mother's mother's mother was non-Jewish).
So even assuming that the DNA test was 100% conclusive as to your DNA being descended from Sephardic Jews (a separate discussion), having DNA that is related to a Jewish group says nothing about one's Jewish status (though it can tell you a lot about your ancestry).
For further information on matrilineal descent, take a look at the answers to this question or this question or at one of these pages: 1, 2, 3
