Genes vs. genealogy

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We are supposed to be 5th or 6th cousins. Some of our ancestors lived in the same area of far western North Carolina at the right time. Back then, the entire western tip of the state around Asheville was a single, large county by the name of Buncombe County. But despite our having well-documented family trees, the common ancestors will not show themselves, and the actual connection pointed to by the genetic data can’t be established.

I have to guess this is a common story for everyone who is attempting to add DNA to the genealogical toolbox.  In this case, « we » are three people, previously unknown to each other. As usual for me with 23andMe, this match appears to be related to the frontier zone where my maternal grandmother’s ancestors mixed, met and married before the move to Missouri that created her own family community. I suppose more data from more participants, especially from cousins like the Justices who remained in the Asheville area, would help us figure out who swapped DNA with whom.

The search for this connection did turn up an interesting bit of trivia, though. Elvis Presley’s ancestors lived there in Buncombe County, too.

Photo of Cold Mountain: Ken Thomas

The Taste of Brussels Sprouts

A few quick notes on the results of my DNA analysis from 23andMe

23andMe got back to me a couple weeks ago, my account automatically loaded with information about health and haplotypes. There’s been a lot to digest, and a weird sort of social media experience, like being on a facebook where people only care about surnames and SNPs and only poke you to suggest sharing genomes.

And oddly, my main recurring thought has been, « but I like Brussels sprouts! »

The first thing I checked was the Y-DNA haplogroup, the clue to my paternal ancestry across the millennia. Haplogroup R1a1a. Spent the last glacial maximum in the Black Sea refuge. The most common haplotype in Eastern Europe. No surprise there, but a lot of material to cover in future posts. Since I spent most of my life not even knowing what my father looked like, I tend to be obsessively curious about his background.

Then the traits – that lactase question. Genetically, milk has no quarrel with me. If there are issues when I eat dairy, it’s not my ancestors’ fault. Bitter taste sensitivity was a surprise, because I’ve always loved broccoli, and at least as an adult, I’ve been a fan of Brussels sprouts. It’s true they can be bitter. In fact, I realized that they taste a lot like a pint of Guinness. That this trait is genetic has actually been understood since the 1930s, and actually used to be used as a paternity test!  What doesn’t make any sense to me is the absence of discussion about olives. People with this bitterness sensitivity can’t possibly like olives, but certain green vegetables are always held up as the main victim of this trait. I actually feel guilty about not liking olives, because they’re supposed to be so good for you, and it’ll be a relief to blame this on a genetic trait.

Finally health, or really, threats to health. 23andMe won’t let you see the Parkinson’s and Alzheimer’s risk until you read yet more info and deliberately « unlock » the file. My risk for Alzheimer’s is 4 in 100, as compared to your average American’s 1in 100 risk. That was the worst of it. With a pretty clean family record in dementia of any kind in my long-lived grandparents and near relatives, it’s not something that will worry me. There were slightly elevated risks for Parkinson’s, heart disease, and Type 1 diabetes. Thankfully, most of my lifestyle choices are ones that should allow nurture to offset nature. Coffee drinking, for example, has been found to correlate with later onset of dementia, and better memory retention even if it does set on. And my doctors are always happy with my calm heartbeat and healthy blood pressure.

Where is the less than average risk? Most of the conditions my hypochondria throws at my imagination when I’m not feeling well. So much for that.

The last category of information, the least relevant to me since I don’t have kids, is the part about what your genes carry and may pass on. In my case, zilch. No congenital defects, no quirks, none of the stuff that made House so fascinating to watch (hemochromatosis, for example).

The taste of olives

23andMe sent an email to say that they received lots of kits at the same time as mine, and it will take them longer then usual to get around to the processing. Must have been a popular Christmas present.

While I wait for analysis, I’m invited to familiarize myself with the 23andMe online experience by means of the Mendel family. This is a real family (but hidden behind Gregor Mendel’s name) of European extraction, whose DNA analysis serves as a typical sample of what the customer should expect to find when their data is loaded into their account.

I find that Greg Mendel is probably lactose intolerant, but his spouse should not be, at least not for genetic reasons. This is what I looked for first, because it’s one of the things I’m looking forward to the most. This information is listed under Traits, along with a lot of other things that are interesting, but not life-changing. Well, that depends on how you feel about ice cream. Or eating broccoli (perception of bitterness). These are all things you already know about yourself when you’re 48. Or do you? In the case of lactose, you may be genetically OK for it, but have other issues preventing its digestion. If I’m lactase typical (and therefore lactose intolerant) it will be time to just stop torturing myself with the possibility of trying that new gelato shop around the corner from Helms Bakery. If it turns out lactose shouldn’t be a problem by virtue of my genes, I can try to find out what my limits are. Maybe it’s really beano I’ve been needing lately, not lactaid?

There are lots of things in the Traits section I didn’t know about before. One’s level of caffeine addiction, for instance, and whether ear wax is wet or dry. I suppose some of this stuff would be good for parents to know. Why force kids to eat Brussels sprouts if the taste is truly offensive to them? Personally I was hoping to see olives listed somewhere, they are a food that really tastes disgusting to me, while my mom will happily eat a whole can during a holiday dinner. One of my cousins likes them, another doesn’t. That has to be a gene thing. Instead of olives, the list said “dark beer.” I love dark beer, even though it is unarguably on the bitter side. Maybe I can get 23andMe to add the olive question to one of their surveys or experiments. Not liking olives makes me feel guilty in a way that avoiding milk does not. Olives are supposed to be really delicious and good for you. On the other hand, broccoli and Brussels sprouts rank really high on my list of delicious, eat-raw-right-out-of-the-garden vegetables.

So all these traits you can learn about are good for chit-chat over lunch. The next two categories of genetic destiny are a little more serious. I’ll save those for next time.

Mutation Free for 7,500 Years

We have just found out a bit more about our place in the U2 haplotype, and in the FTDNA community. Thanks to information kindly supplied by the FTDNA Haplotype U2 Project coordinator, the picture has become more clear since the time we had the full mitochondrial sequencing (FMS) done.

My mom’s mtDNA puts her in a subclade that is rather rare. Among the known samples, it has not acquired any mutations for 7500 years, making it difficult to place geographically. Two other known samples are related to Britain and Ireland, and the long presence of U2 and U2e in prehistoric Europe is well known. In 5500 BC or therabouts, the farming practices of the Neolithic were finally moving beyond Greece. Hunter-gatherers still occupied the majority of the continent. Life expectancy among the Neolithic farmers was 20-25 years of age, and 50% of children didn’t make it to 15. Even so, one imagines that the farmers thought themselves better off than the ones who didn’t farm. The question that remains to be answered is how many of the Neolithic people were incomers, as opposed to how many were adopting the new culture.

One zooarchaeologist, Nerissa Russell, has conjectured that the use of cattle as bride-wealth may have eased the spread of the Neolithic farming economy as it moved through an already-inhabited Europe. This is one way that pre-Neolithic genetic lineages may have survived the immigrants.

Until there is a lot more mtDNA evidence, it will be difficult to determine how clade U2e came to be in Europe. Most of U2 is actually found in South Asia. But this haplotype is so ancient that there would have been plenty of time for U2e women to move slowly west, arriving well before the European Neolithic. Or perhaps they moved just far enough west to move into Europe along with the Neolithic pioneers.

From the other direction, from the present, it’s pretty certain my mom’s foremothers lived either in the British Isles or western Europe (probably the Rhineland) in the centuries before emigrating to North America. In terms of genealogy, this hinges on the origin of a woman whose married name was Esther North. In colonial Virginia’s Shenandoah Valley, settlers from Germany mixed with English and Scotch-Irish settlers, so Esther’s origins could go either way. Her daughter married the son of an immigrant from Switzerland, and their daughter married the son of immigrants from Westphalia. We are really lucky in that these families have been very well documented by very hard-working genealogists.

There will come a point when the historical record just won’t be there for my line of foremothers, and that provides a big motivation for participating in mtDNA analysis. Right now I’m hoping that genetic testing will get really trendy so that enough data will become available to fill in the gaps, not just in prehistory, but in the historical times where ordinary farming folk aren’t documented.

Pandora’s Box

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The DNA adventure begins with 23andMe. As the sun goes down on the first day of 2013, I’m getting ready to fill up a little sample bottle with spit. I’ve been solemnly warned about the possible consequences of opening this box. “You may learn information about yourself that you do not anticipate. Once you obtain your genetic information, the knowledge is irrevocable.”

It is to be hoped that no one is ordering these kits without already having given that some thought. At 48, free of major scary diseases, and with none on either side of my family, I’m pretty confident I can handle what surprises may be left. Those who know my tendency to hypochondria and anxiety would probably prefer I stuck to the ancestry side of this information. But the thought of contributing data to scientific research is too tempting. I’ve been reading the research produced in archaeology with human and animal DNA studies for some time now, and it’s an exciting field. Of the negative consequences, insurance companies using this information against me in some way is my biggest concern – but again, given the fine state of health of me and my nearest relatives, it’s just a concern, not a worry.

On the other hand, this next foray into DNA analysis may not turn out to be that much of an adventure after all. It’s been a couple years since my mom’s mtDNA was analyzed. At that time, Family Tree DNA was the option I picked, and it was a Mother’s Day present. With genealogical records tending to favor male ancestry, I really thought we should have some insight about deep maternal ancestry. As expected, it was European (but there was always a slight chance of origins on two other continents, since my maternal grandmother’s ancestors were colonists and frontier people in North America from 1622 on). And it was really European. According to that test, my mom’s maternal ancestry reaches back to a now-rare haplotype that is associated with the earliest paleolithic inhabitants of Europe. And a lot of other places as well, like South Asia. 55,000 years is a long time! Also as I’d hoped, there were indications of correlation with some Gaelic surnames, but as with all DNA analysis, it’s hard to know what these things really mean in a concrete, significant, historical way.

We also get email every time a “match” turns up, but so far this has not led to any stunning genealogical revelations. A match is a possibly very distant cousin, whose relationship to my mom probably predates the relevant historical records. It’s hard to find time to add yet another bunch of action items to my already neglected inbox (it’s a system I call Thinking About Getting Things Done). One of my goals for this little break from professional life in between semesters is to catch up with several family history projects. Exploring the Family Tree DNA “matches” is one, and 23andMe will be another. Then there’s the old-fashioned hard work of paper trail genealogy that needs to get brought up to date as well.