DNA Makes for Strange Bedfellows

by Finding Your Roots Genetic Genealogy Consultant, CeCe Moore
SPLIT SCREEN with words

Episode two of Finding Your Roots: Season Three featured Bill Maher, Bill O’Reilly and Soledad O’Brien, and allowed us to deep-dive into Irish genetic genealogy research. Working with so many people who possess such varied ancestral backgrounds has provided me with the unique opportunity to learn about DNA from different parts of the world in a way that wouldn’t be possible otherwise. During this work, I frequently see evidence of exactly what Dr. Gates noted, in both humorous and serious ways, “DNA makes for strange bedfellows!”

Contrary to what some may believe, separating out “Irish DNA” from that of the rest of Northern Europe is not a straight-forward exercise and, often, not even possible. However, Y-chromosome DNA can sometimes be an exception to this, thanks to the extensive research done by both academics and “citizen scientists” from our own genetic genealogy community over the last decade and a half. I don’t think it is an exaggeration to state that Y-DNA from the British Isles, particularly Ireland, is among the most studied and tested in the world.

R1b-M222 map

R1b-M222 map

As revealed in this episode, the direct paternal lines of both Bill Maher and Bill O’Reilly originate in Ireland so, unsurprisingly, their Y-DNA carries a well-known “signature” that is most often found among men of Irish descent. As Dr. Gates told Bill Maher in the episode, his own Y-DNA falls within the same haplogroup subclade as both of the Bills. This subclade is R1b – M222, which is defined by a positive result for the marker named M222. It has long been theorized that the millions of men who belong to this Y-DNA subclade can trace their direct paternal lines back to a legendary Irish king who is believed to have lived approximately 1,600 years ago, “Niall of the Nine Hostages” (although recent advancements in research may put this claim in doubt).



There are two types of Y-DNA markers that we use in genetic genealogy to inform us about a male’s direct paternal line. They are called SNPs (single nucleotide polymorphisms) and STRs (short tandem repeats). Shared haplogroups, which are defined by Y-SNPs, imply a direct paternal line common ancestor between two or more men relatively distant in time, prior to what we typically consider a genealogical time frame. In contrast, a long string of shared Y-STRs, indicates a common ancestor more recently, often within a genealogical time frame.

In the cases of Maher and O’Reilly, their Y-DNA signatures are so similar that they likely share a common ancestor significantly closer in time than with other men who carry the M222 SNP, like Dr. Gates. It isn’t possible to determine exactly who that common ancestor was or when he lived, but we do know that it is highly likely that he lived in the ancient Kingdom of Breifne, sometime between the eighth and thirteenth centuries. This kingdom was sandwiched between the two areas ruled by the Uí Néill families who claimed descent from Niall of the Nine Hostages, so not inconsistent with what we learned from their haplogroup subclade. There is a DNA project created specifically for males who are descendants of the clans of Breifne, helmed by the terrific Gail Riddell, and both O’Reilly and Maher were identified as eligible for membership.

O'Reilly Family Tree

O’Reilly Family Tree

I wouldn’t want to be the one to tell Bill Maher this, but the O’Reilly kings triumphed in the battle of 1256 for control over the area of East Breifne that later became County Cavan (which happens to be where O’Reilly’s most distantly known direct paternal ancestor originated). So, not only can O’Reilly boast of descent from King Niall of the Nine Hostages, but probably from the O’Reilly kings of Breifne as well. It might console Maher (or not) to know that both men’s Y-DNA matches other O’Reillys and neither matches any other Mahers. The major difference between their two Y-DNA signatures fell on highly volatile markers, which could mean an even more recent connection than it appears from a superficial review. To support this possibility is a match of another kind.

For all the guests of the show, I run autosomal DNA (atDNA) comparisons against everyone else in our database to see if they share atDNA with any of the other guests from Dr. Gates’ series. Autosomal DNA is inherited from all of our ancestral lines and, therefore, is informative of common ancestors on lines other than just the direct paternal line. While analyzing the DNA results for these guests, I was chuckling at the idea of the two Bills matching on their atDNA. I didn’t expect to get that lucky though since it is somewhat unusual for me to find a match between any two guests (outside of the ones with Ashkenazi Jewish ancestry). So, when I ran the comparison and saw the colored segment indicating shared atDNA between them, I literally jumped out of my chair for joy. Long hours are spent digging for entertaining DNA stories and this one felt like a true gift.

This meant that Maher and O’Reilly had not only similar Y-DNA signatures, but also a significant stretch of identical atDNA. The ancestor responsible for these two different types of DNA matches may have been the same one, or the two Bills may share multiple ancestral lines from Ireland. Autosomal DNA matches detected by the companies we use for our comparisons are generally believed to indicate a shared ancestor in the last several generations. This was not a large match, however, so it is possible that it reaches back to an ancestor from the time of the ancient Kingdom of Breifne, but not likely. Either way, this supports what genetic genealogy so often teaches us – we are all connected and, many times, a lot more closely than we might imagine.

Soledad O’Brien’s family believed that they too had a connection to an Irish king through their direct paternal line. He was the High King Brian Boru who was born in the middle of the tenth century. For that to be true, we expected her family’s O’Brien Y-DNA results to be similar to those of Maher and O’Reilly in that they would reveal a well-established, recognizable Irish Y-DNA signature. In this case, the genetic connection wouldn’t be just in theory since the O’Brien DNA Project actually has the Y-DNA results of a documented, direct paternal line descendant of King Boru (who has had his lineage confirmed through matches with other O’Brien men). Unfortunately, Y-DNA testing of Soledad’s brother revealed no genetic connection to this lineage. Instead of sharing a Y-DNA signature with this man or even some of the many O’Brien males who have been tested, 29 of his 31 matches carry the surname Ricketts – not very Irish sounding at all. The direct paternal lines of these matches were either from England or genealogically brick walled in the United States.

Research on her autosomal DNA results showed relatively close matches sharing her recent O’Brien line (predicted 3rd-4th cousins) and only distant atDNA matches with individuals who had the Ricketts surname in their family trees. From this, I concluded that this name change or disconnect in her direct paternal line (sometimes called a non-paternal event, although I prefer the term misattributed paternity) was likely multiple generations back in her direct paternal O’Brien line and not a recent occurrence. This is a reminder that DNA will sometimes reveal secrets that the paper trail cannot. Fortunately, Soledad’s Irish genetic connections didn’t prove difficult to find, however, and we were pleased to be able to identify an atDNA cousin from among our former guests for her as well — Stephen Colbert.

I have been receiving a lot of questions in regard to the admixture pie charts for the guests, so I am including them below.

I am really looking forward to the third episode, which unveils a surprising shared secret revealed through the DNA of guests Maya Rudolph and Keenan Ivory Wayans as well.


Bill Maher’s Admixture Results



Bill O’Reilly’s Admixture Results



Soledad O’Brien’s Admixture Results