Understand 12-marker matches - Surname of Color

[cclarke]

New to the forum.

I bought a 37 marker Y DNA test for a distant cousin to help him identify his biological surname. Note that his line(s) descends from slavery.

We were both very disappointed to see only 12 marker matches. He has no listed matches at the 25 or 37 marker levels.

I've been told 12 markers are only noise. However, I can't help but wonder when the majority of the matches are the same haplogroup (R-269) and 2 surnames are predominant. Note that those 2 surnames (Ballou/Guthrie) intermarried.

All 12 marker matches are 0 genetic distance. And, my distant cousin matches one Ballou/Guthrie perfectly on all 12 markers.

Also, note that he has 3 matches for another surname (Scruggs). One of the matches was noted as a line of color. He also matches at least one of these perfectly at 12 markers.

All 3 surnames were in the same part of Virginia in the late 1700s.

Is it true that all of these 12 marker matches aren't valid? Or, can we draw some inferences or conclusions from them?

Any thoughts/advice is greatly appreciated.

[georgian1950]

If any of those 12 marker matches tested 25 or 37 and you do not match at the higher level, forget about it. If one only tested Y-12, you need to approach them about testing Y-37.

Jack

[dna]

This is beyond my usual area of interest, so I can offer only two generic comments based on fundamentals of genetic genealogy research.

Family Finder (FF) would be a good choice to supplement his completed Y DNA testing. (This is not a commercial ad, it is a fact.) If he has siblings, he should ask them to help him. With FF they can help regardless of their sex. But nothing is simple regardless of the type of the DNA test.

FTDNA does not have a uniform coverage of the USA population. Some sub-populations are over-represented, and some are underrepresented. The reasons are varied, sometimes it is a higher level of interest, sometimes there are preconceptions against any participation. If you think that is weird, please realize that for example France (country) is imposing severe limitations on DNA testing, so clearly different views are possible. The above is important, since if nobody who is a descendant of his ancestors of interest tested here, he would have no close matches regardless how much he tries. However, such a descendant might test one day! Additionally, there is a non-zero possibility that he is the only one living in the ancestral line he is trying to discover.


Good luck in your research - Mr. W.

[prairielad]

If you join your Haplogroup project you will also see matches at the 12 marker level which show as a GD of 1, if these matches are members of same project.

https://www.familytreedna.com/my/group-join.aspx?group=R1b&ekit=%2bzRCsIKoQbrm7yraSzE5sQ%3d%3d

12 marker level matching with no matching at the 37 marker level does question the validity of these 12 marker matches being of use genealogically. It means there is over 4 differences with these matches at the 37marker level (37 marker level allows up to 4GD)

https://www.familytreedna.com/learn/?s=If+two+men+share+a+surname&__ncforminfo=mMWvdk910nRktm5BDi_qYjZJCsgq0ysfsKlbIwODJMTh5wbZYY7JpsBDWKzIlMXzAAPexdYeT5O62tEdw2Kk5GkdNW765Yr5Q9cga210IVs%3D