Do I have Jewish ancestry on my direct paternal (Y-chromosome DNA) line?

Judaism is a religion and not an attribute definable by a DNA mutation, but we can give you hints about having Jewish ancestry by comparing your results against our database. Look on the Y-DNA – Ancestral Origins page to see whether or not the people you match have listed Jewish ancestry. Those in our Jewish database have a listing in the Comments column denoting Jewish ancestry. There are four situations when testing for Jewish ancestry. [...]

How does the nature of Jewish genealogy make autosomal DNA research more challenging?

Using Family Finder results for genealogy is more challenging for individuals of Jewish ancestry because of a lack of genealogical records, surname changes, and frequent intermarriage.

The lack of genealogical records means that finding the connection with even a third cousin may not be possible. It is important then to focus on those matches who come from the timeframe of available records.

Name changes are, as always, one of the biggest challenges of Jewish genealogy. Here is [...]

How does the nature of Jewish genealogy make Y-DNA research more challenging?

Because Jewish genealogists cannot assume that paternal line ancestors have had the same surname for over 300 years, interpreting close and exact matches requires more thought and consideration than would otherwise be the case.

Where a non-Jewish genealogist with origins in a country such as England might see an exact Y-DNA37 match with the same surname and use it to confirm a recent relationship,  Jewish genealogists must approach it more cautiously. They need to consider [...]

How does Y-DNA help with the challenges of Jewish Genealogy?

Unlike many other populations, the Jewish people adopted hereditary surnames relatively recently. Surnames changed during recent emigrations. Some families modified their surname spellings to fit with local norms. By testing the Y-chromosome DNA, you and your cousins can recover the linkage along a direct paternal line.

For example, someone has the surname Brown. They also have a family tradition that their ancestors and their cousins who moved to Australia and South Africa were Plikhs. By [...]

Is my direct paternal (Y-chromosome DNA) line Cohanim?

Because the Jewish populations of the world have suffered many trials and population upheavals, it is not possible to say definitively that one person is genetically Cohanim while another is not. However, scientific papers over the last decade have shown that many men with a family tradition of being Cohanim belong to the same genetic Y-chromosome lineage. This is the Cohanim Modal Haplotype (CMH). In popular culture, it is sometimes misnamed the Kohanim Gene.

If [...]

Do I have Jewish ancestry based on my Family Finder and myOrigins results?

Judaism is a religion and not an attribute definable by a DNA mutation, but we can give you hints about having Jewish ancestry by comparing your Family Finder results to those of known Jewish ancestry in our database. myOrigins results may also provide clues to recent Jewish ancestry in the last five generations.

The first clue to your having recent European Jewish ancestry is the number of matches you have in the Family Finder database. [...]

How do I tell if I have Jewish ancestry on my direct maternal (mitochondrial DNA) line?

Judaism is a religion and not a genetic attribute that can be defined by a DNA mutation. However, because Jewish populations have been endogamous for much of their history, hints to your Jewish ancestry for your direct maternal lineage are provided by looking at the mtDNA – Ancestral Origins page in your myFTDNA account. Check the Comments column on this page. There are four possible situations:

You match only people who are Jewish. You will [...]

What percent of Jews carry the Cohanim Modal Haplotype (CMH)?

From surveys of markers in Jewish cemeteries, about 5% of Jewish men have historically been Cohanim. Genetic research indicates that many Jewish men who self-identify as Cohanim belong to the Y-chromosome DNA lineage that is most common in the Cohanim. That is, they belong to the Cohanim Modal Haplotype (CMH). Further, in a study conducted in Israel where men were asked at random if they were Cohanim, Levite, or Israel, of those answering Israel, [...]

What is the Cohen Match badge?

If you have a Cohen Match badge on your myFTDNA dashboard, it means that you match or are close to the historic Cohen Modal Haplotype (CMH). One of the earliest Y-chromosome population genetics studies documented the CMH.
In 1997, Journal Nature published a study that showed that a high percentage of Jewish males who shared an oral tradition of being Cohanim also shared the same Y-chromosome signature. The authors named the highest frequency Y-chromosome signature (haplotype) the Cohen Modal [...]

What are the challenges of Jewish genealogy?

Jewish genealogy includes many challenges that mean more frequent and problematic road blocks for the Jewish genealogist than for the non-Jewish genealogist. The following are some of these challenges:

Surnames that pass from father to son were not adopted until the late 1700s and early 1800s.
Unrelated paternal lines have adopted the same surnames.
Related paternal lines have adopted different surnames.
Surnames have been adapted to the country where descendants live today.
In many cases, traditional [...]