Monday, October 28, 2013

Gentlemen, sorry but... size DOES matter !!!

Bigger really is better!   And I must admit that when I see a nice, big one I get excited.....Anything less than 7 is insignificant and really not worth pursuing.

7 cM that is.  I'm talking about centimorgans (cMs).  What did you think I was talking about???

I realize that some genetic genealogists place value in smaller than 7 cM segments, and I *DO* understand that sometimes segment shares smaller than 7 cM are in fact IBD (Identical by Descent) and not IBS  (Identical by State).  But, with 14 kits with results and counting at 23andme, I have only so much time, and I prefer to focus on the bigger matches for now.

Most of the kits I manage at 23andme have hit the 1000 DNA relatives cap long ago, and no longer receive 7cM matches, but they do occasionally show up as they are sharing a larger segment with another kit.

I enter all matching segments, regardless of size, into my spreadsheets, but usually only focus on trying to find a common ancestor with larger matches.  An exception to this is if the segment is shared by multiple people, or I already know the ancestor I got that segment from.

No clue what I'm talking about?  I'm talking about autosomal DNA testing...try it! Read more about it here