Why different Y DNA Haplogroups for these related men?

[Catherine McKay]

Hi,
I am a newbie and I have a question about Y DNA haplogroups. I had my brothers Y DNA tested at Family Tree DNA and the Y DNA haplogroup came back R-M269. I also had his autosomal DNA tested and it showed matches with a cousin who is descended from our paternal line through a daughter. I later had my DNA tested at Ancestry and I match many of the cousins from our paternal line who had been tested at Ancestry. I have a large tree based on paper research and I know them to be cousins and now we match on DNA. I had a DNA test done at 23&me. Many of my paternal cousins show up at that site. They are cousins on paper and also DNA. Lately I noted at 23&me that there were males of our paternal line with same surname as my brother and myself. They match me autosomally they are said to be my 3rd cousins. I know that we are descended from same 2 great grandparents. But, there Y DNA haplogroup is R-L21 while my brother is R-M269.So what is problem?
Catherine

[rmm0484]

Hi,
I am a newbie and I have a question about Y DNA haplogroups. I had my brothers Y DNA tested at Family Tree DNA and the Y DNA haplogroup came back R-M269. I also had his autosomal DNA tested and it showed matches with a cousin who is descended from our paternal line through a daughter. I later had my DNA tested at Ancestry and I match many of the cousins from our paternal line who had been tested at Ancestry. I have a large tree based on paper research and I know them to be cousins and now we match on DNA. I had a DNA test done at 23&me. Many of my paternal cousins show up at that site. They are cousins on paper and also DNA. Lately I noted at 23&me that there were males of our paternal line with same surname as my brother and myself. They match me autosomally they are said to be my 3rd cousins. I know that we are descended from same 2 great grandparents. But, there Y DNA haplogroup is R-L21 while my brother is R-M269.So what is problem?
Catherine

As I thought, L21 is a subclade of M269, which means that they are related, but certain variations caused them to be classified within the subclade rather than the main group.

https://en.wikipedia.org/wiki/Haplogroup_R-M269

[John McCoy]

All that can be said at this point, is that there is no evidence that they belong to different "subclades", based on SNP's that have been tested (or possibly, inferred). So, there is not yet any evidence presented that indicates a discrepancy.

Are there STR data for both men? If so, do all of the STR's match?

[spruithean]

Because 23&Me tests SNPs while FamilyTreeDNA's Y12,25,37,67,111 tests only test STRs.

If these men all share STRs in the FTDNA database they will show as matches. Testing the proper SNPs will confirm the haplogroups.

[The_Contemplator]

The 23&me test is mostly an autosomal DNA test with some YDNA and mtDNA markers tested. They don't test the Y-STRs but some Y-SNPs. The FTDNA YDNA STR tests are giving you a safe prediction on your brother's haplogroup but do not actually do a SNP test. The 23&me test is not testing the M269 SNP, but does test the L21 SNP. So they could very well be from the same haplogroup. You are just comparing apples and oranges as they are not being tested on the same type of markers.

Testing the 23&me match with a STR test would tell you if he matches your brother. He might, but we can't know for sure without actually testing.

[spruithean]

One individual has done more SNP testing via 23andMe, the FTDNA customer has only tested STRs which can simply estimate a haplogroup, and when dealing with R-M269 it will not be as accurate as SNP testing when it comes to determine terminal SNPs.