Finding Fathers: Decoding the Y-Chromosome

by Finding Your Roots Genetic Genealogy Consultant, CeCe Moore

Y CHROM
For last week’s episode, we researched the family trees of three people who yearned to know more about their paternal ancestry – Courtney B. Vance, Stephen King and Gloria Reuben. As a genetic genealogist, the first thing that comes to mind when I hear that there are paternal mysteries to unravel is that Y-chromosome DNA testing is a must.

Since the Y-chromosome is passed directly from father to son, analyzing the clues contained within it can reveal potentially valuable and relevant information about the direct paternal ancestral line of an individual’s family tree. Since the Y-chromosome and surname inheritance in many societies follow the same path, we can at times determine the “genetic surname” of an individual by comparing his Y-chromosome to that of other males. For example, a male adoptee can often discover the surname of his biological father through Y-chromosome testing.

The Y-chromosome is inherited directly from father to son. Image courtesy FamilyTreeDNA.com

The Y-chromosome is inherited directly from father to son. Image courtesy FamilyTreeDNA.com

My first step in researching the genetics of these three guests was to request that each of them participate in Y-DNA testing. Of course, only males carry this type of DNA signature, so a woman seeking this information must test a male relative from her direct paternal line – in Gloria’s case this was her brother. Courtney, Stephen and Gloria’s brother were each asked to swab the inside of their cheek and return the sample to the lab. When we received the results, I was excited to see that for each of them, the findings were illuminating. While most of the details of this analysis didn’t make it into the final episode, I thought readers would be interested in learning more about what the Y-DNA tests revealed.

As shown in the episode, Courtney’s Y-DNA was a perfect match to a man with the last name Arrington. This man traced his direct paternal line back to the Arrington Plantations of Alabama and North Carolina. As is typical, some of the enslaved individuals owned by this family adopted the surname Arrington, including the ancestor of this match. While it is not usually possible to reach a definitive conclusion from a Y-DNA match to a single individual, this one turned out to be potentially significant. At the time of (Courtney’s father) Conroy’s conception, his mother (Courtney’s paternal grandmother) was living in very close proximity to several African American Arrington families with male sons, leading us to believe that perhaps one of them was Conroy’s father. We pursued further DNA testing with this theory in mind, but in the relatively short amount of time we had to research, we were unable to resolve the question of the paternity of Conroy Vance. Although the answer is still elusive, Courtney’s Y-chromosome has offered a precious clue to further pursue this family mystery.

I found Stephen King’s result enlightening as well. As was mentioned in the episode, Stephen’s father had changed his surname from Pollack to King. Well, if there had been any doubt about that, then his Y-DNA results would have cleared that right up for us! Stephen had strong Y-DNA matches to nine men with the surname Pollock and several others with surnames that appeared to be derivatives of it – Polk, Pogue and Poland! This fact was not mentioned in the episode because it was not an unexpected revelation, but I personally found it meaningful because it demonstrated the power of Y-DNA testing: a man may change his surname, but his Y-chromosome doesn’t change. As a result, with the tool of Y-DNA testing, it is impossible to hide the truth from an inquisitive genetic genealogist!

Gloria’s paternal line’s genetic signature was perhaps the most intriguing of all. Her brother’s Y-DNA was a match to a historic Sephardic family with direct ties to the Lisbon Inquisition. A member of that family was a well-known slave trader in Jamaica. It is unknown how Gloria’s paternal ancestors connect to this man, but her brother’s Y-DNA signature leaves little doubt that they do.

Just as the Y-DNA of the three families featured in Episode One: In Search of our Fathers revealed clues to the past, so it will for one of the special guests in Episode Two – Yankee captain Derek Jeter. Don’t miss Tuesday’s episode to find out more!