Tag Archives: autosomal DNA

The Generation Gap in Autosomal DNA Testing

I’ve been asked again, “How far back will DNA testing take me?” That’s a great question with kind of a complicated answer.

Autosomal testing is the kind of DNA test that both women and men can take. It’s offered as AncestryDNA and Family Finder on FTDNA.com. FTDNA is pretty clear about the possibilities (or the glass is half empty side) of testing.  FTNDA says it will match up within 5 generations (see their site).

I’ve been pretty lucky I guess because on Ancestry I’ve had some pretty good matches at 6th generation.

How does it get complicated? Well this weekend I searched an unusual surname in the Ancestry results and came up with someone by that name. The were a wishy-washy “GOOD” ranking in the results. That didn’t seem very promising, but I reached out to them anyhow. Sure enough, we pieced together we were related.

If we are related why did we have only a “GOOD” result? Genetic distance plays a role. Our shared ancestor is 3 generations from me and 7 generations from my match!

The size of the Generation Gap also plays a role. My branch of the family tree has children every 40 years (not the accepted norm of about 20 years per generation. My match’s branch has children within the 20 year generations. I drew out a chart to show how far we’re separated because of the length of our generations. My great grandfather is this person’s great-great-great-great grandfather. That’s right the “Shared” ancestor in each line of the chart is the same person.

As a child I’d spend sick days home from school with my grandpa and hear stories of the old days and he was able to tell me who was whom in family photos. I’m a link to the past for my match that they never expected when testing. It’s a match I wasn’t expecting

It helps to reach out to results to see how you may be connected.

If had known that autosomal testing was limited to perhaps 5 generations, I would have asked all of my oldest relatives to test!

Category: DNA | Tags: