Thursday, 13 August 2015

Do you have the Western Atlantic Autosomal Haplotype?

If you've taken an autosomal DNA test with Family Tree DNA you might want to check out a segment on chromosome 2,  It starts at about 134334310 going to about 137632795 and containing 2.6 cM or 798 SNPs.

According to an article Minimum Inherited DNA Segment Size and the Introduction of Familial Autosomal Haplotypes, by Michael R. Maglio, this segment correlates to a Western Atlantic ethnicity. He terms it the Western Atlantic Autosomal Haplotype.

Checking my own top five autosomal matches three matched me on that segment. None are known relatives, none estimated as closer than 2nd to 4th cousin, each has British or Irish ancestry. Out of my 1460 matches 101 people matched me on that segment.
Although my matches are at the same location on chromosome 2 there's no way of knowing if the SNPs are the same as Maglio found.

Many people are skeptical about autosomal matches on small segments. I'm cautious. The article by Maglio isn't peer reviewed.

 It would be interesting to know if others have multiple matches at the location of this small segment.

8 comments:

Anonymous said...

Is there a quick way to check all your matches? I.e. How did you check all 1450 matches?

JDR said...

From your Family Finder - Chromosome Browser click on Download All Matches to Excel (CSV Format) then sort in Excel primarily by CHROMOSOME and secondarily by START LOCATION.

Elizabeth Kipp said...

I have 535 matches at FT DNA. I have 14 matches that fit into that particular length. My brother on the other hand has 592 matches and 33 matches that include the particular length. My sister has 559 matches and 40 matches to this particular length. My siblings and I have 100% British Isles ancestry. My husband has 601 matches and 144 matches that includes the particular length. Given my husband's primarily European ancestry (British Isles is only around 10%, Germanic 60% (includes The Netherlands/Denmark/present day Germany), French 30%) this could be a rather interesting study.

Holly said...

I am thrilled to have found your website. As an American with Glengarry, Ontario ancestors, this is so very pertinent to me! I've done Ancestry DNA and uploaded to GEDCOM, but must admit that I don't really understand how to make sense of the DNA info. Would I be able to check this info through GEDCOM?

Holly said...

OOps, I meant GEDMATCH not GEDCOM -- yes, I do find it confusing.....

Wendy Croome said...

I have 677 matches but none from exactly 134334310 to 137632795 on chromosome 2. I do have 57 matches with shorter segments that fall within those start and end points. As far back as I have discovered, my ancestry is 100% British Isles.

Wendy Croome said...

I just checked 2 cousins and found that both have more matches than I do within that length of chromosome 2.

Cousin 1 = 680 matches including 137 matches within that segment. Ancestry is primarily British Isles.

Cousin 2 = 993 matches including 319 within that segment. British on her mom's side and I think British on her dad's but I'm not sure.

Debbie Kennett said...

Small segments like this cannot be used for genealogical matching purposes. The vast majority of these small segments are false positive matches. There is lots of information on small segments, including links to articles in peer-reviewed journals, in the ISOGG Wiki:

http://www.isogg.org/wiki/IBD

There's also been a lengthy discussion in the ISOGG Facebook group about this self-published paper which has highlighted the numerous flaws in the methodology:

https://www.facebook.com/groups/isogg/permalink/10153580852647922/