Will the Duggars Inherit the Earth?


In which I am inspired by a snarky comment on another blog.

My normal routine involves a fair amount of procrastination, but I tell myself that's OK (really), because sometimes it leads to work ideas. Like, a couple of months ago, when I was browsing through the Onion AV Club and stumbled over the headline, "By 2100 Everyone Will Be Part Duggar."

Naturally, my response was to wonder whether that might actually be true. After all, back in 2003, researchers figured out that 8 percent of all men living in central and east Asia--a huge proportion of the global population--are likely descendants of Mongol ruler/horde-leader Genghis Khan. I contacted some of the researchers involved in that project to find out whether we can project that kind of genetic impact forward in time as well.

Image courtesy TLC.

The answer: Kinda-sorta.

"It's really just a little simple math," said Spencer Wells, Ph.D., Explorer-in-Residence with the National Geographic Society, working on their Genographic Project, which traces human migration patterns by studying DNA markers. "If you imagine that each of the Duggars' 19 kids has 19 kids, for only four generations--that's only going for 100 years--there would be 130,000 descendants of this one couple."

But, at the same time, it's not as easy as all that. Wells, and colleague Chris Tyler-Smith, Ph.D.,head of the Human Evolution team at The Wellcome Trust Sanger Institute, said it's too early to tell what the Duggars' genetic impact on America will be.

Let's look back at Khan again. And clarify things a bit, while we're at it. It's important to point out that nobody knows for certain that 8 percent of Asian men are descendants of the Mongol leader. What we know is that those men share a collection of genetic mutations--a haplotype--on the Y chromosome, which suggests that they all shared a common male ancestor.
Y chromosomes are passed from father to son intact, without the shake-n-bake interference of maternal DNA. So Y chromosomes don't get remixed each generation, but they do, occasionally, pick up a small change here and there from random mutation. Scientists know roughly how often those mutations happen, so they can look at a haplotype, see how different it is from the general population, and get an idea of when that family group broke off from the herd. In this case, the point of origination would have been about 1000 years ago, give or take.

Scientists associate the haplotype with Genghis Khan not because all the men who share it have a predilection for little furry hats, but because of simple logical deduction. It's a rare guy who is going to have enough children, and whose children will have enough children (and etc.) to leave such a big mark on such a large geographic area. Historically, we know that around 800 years ago, old Genghis was doing quite a bit of marrying, concubining and raping/pillaging. And we know that his immediate descendants were also powerful men who were able to have a lot of children, with a lot of different women, in a lot of different places. Chris Tyler-Smith explains it thusly,

"So we can either say that there were two separate events: One, Genghis Khan's lineage, which was present in Mongolia 800 years ago and we know was greatly amplified over the next centuries, has disappeared from the current gene pool, while another lineage that arose in the same place around the same time has reached high frequency without leaving any trace in history. Or we can say that Genghis Khan's lineage and the star cluster lineage were the same. To me, this second possibility is the simpler explanation. Indirect, but a bit more than guesswork."

To tie this whole Mongolian warlord thing back to the Duggars, just look at the kids. Genghis' sons, grandsons, and great-grandsons were privileged by his power and wealth. They had the means to support BIG families, and the social capital to acquire those families. In fact, they had the social obligation to breed it up. And, thus, did the not-exactly-meek-and-peaceful Khan inherit most of Asia.

Whether the scientists of 2800 are studying the Duggar haplotype depends on how many babies the 19 Duggar kids, and their kids, have. In this case, it's not necessarily a given that the parents' productivity will be inherited. If growing up in America's biggest TV family leaves most of the kids gun-shy, so to speak, the family could end up with no more of a long-term genetic footprint than the rest of us. On the other hand, there are certainly social and religious factors encouraging the Duggarlets to follow in their parents' footsteps. And, if a large number of them do, and if their kids carry on the family tradition...we could well be on the way to welcoming our Duggar overlords. Genetically speaking.

Side note: In writing this, I kept having to re-check to proper spelling of "Duggar" in the singular, because it looked weird. Because you never see the name in that form.