Shabbat Parashat Miketz 5777

Parashat Hashavua: An Exciting Genetic Jewish Marker

Last week we saw that all of the patriarchs were seriously involved in conversion and thus in welcoming people into the fold. We mentioned that we should look to help three categories of people who live in Israel but could find themselves excluded from the Jewish community. 1) Proving the Jewishness of born Jewish who, due to the horrors that befell the Jewish people in previous generations, cannot prove it. 2) Providing valid conversions for the children of Jewish fathers. 3) Dealing with those without Jewish blood who still were able to enter Israel under the Law of Return. This week we will focus on group #1.

Professor Karl Skorecki of the Technion in Haifa, along with other important scientists worldwide, have proven that approximately 40% of Ashkenazi Jews in Europe are descendants of four Jewish women who migrated with their families to parts of Europe where Jews previously had not lived, more than 1,200 years ago. One can find “footprints” of links to these “matriarchs” in the gene pool today. Let us quickly explain how.

All people receive DNA both from their mother and from their father, and this genetic information is found in the nucleus of all of a body’s cells. A small group of genes, which is different from the rest of the human genome, is not found within the nucleus but “resides” nearby in the cell’s mitochondria. It is called mtDNA. A female’s egg is the largest cell in the human body, and a male’s sperm is the smallest. The mtDNA is in the egg itself but only in the tail of the sperm. In the reproductive process, the embryo receives mtDNA only from the mother, not the father. Thus, the aforementioned four Jewish matriarchs passed on this part of their genetic codes through their daughters to their Jewish offspring many generations later, “untainted” by their male spouses codes. (A male has mtDNA from his matriarchal chain, but he does not pass it on.)

In the framework of supporting the efforts of diaspora rabbis and the Bemareh Habazak responsa project, a European rabbi from one of our “learning groups” asked us the following question: “A woman came to me, wanting to join the community with her children, claiming that she is Jewish. She says she is the granddaughter of a Holocaust survivor, who swore when she left the camp that she would have no connection with Judaism or Jews. She married a non-Jewish man and made sure her children would marry non-Jews. Her daughter’s daughter has presented us with an mtDNA analysis proving genetically that she is a descendant of one of the four founding women of the Ashkenazic communities of Europe.”

Can we rely on these results halachically? When this question first reached us, we realized that this idea has the potential to be very significant for many olim who cannot prove their Jewish lineage. After this discussion of the scientific background, we will deal with halachic analysis next week. Let us just stress at this point that no aspersions whatsoever can be cast on someone who lacks a link to these four women. Most Jews in the world do not have the gene code in question, so not having it does not at all preclude Judaism.

In the meantime, we wish our readers and all of Klal Yisrael a happy Chanuka with an abundance of light.

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