R-L48 and R-M269

[Hollis]

Hello. On gedmatch a man and I share 248.6 CM. He is looking for his biological father, a sperm donor in 1958. His paternal Haplogroup is R-L48. My brother's (at 67 markers)is R-M269 on FTDNA. My question is can these two men share a male line? Neither the man nor I know much beyond the very basics of Y testing. If I had more testing done on my brother could it show the same haplogroup as this man? Or is this not a possible match? If not, then I can cross off that male line as a match to him. Thank you for your time. Susan Hollis

[MMaddi]

Originally Posted by Hollis

Hello. On gedmatch a man and I share 248.6 CM. He is looking for his biological father, a sperm donor in 1958. His paternal Haplogroup is R-L48. My brother's (at 67 markers)is R-M269 on FTDNA. My question is can these two men share a male line? Neither the man nor I know much beyond the very basics of Y testing. If I had more testing done on my brother could it show the same haplogroup as this man? Or is this not a possible match? If not, then I can cross off that male line as a match to him. Thank you for your time. Susan Hollis

On GEDmatch my sister shares 304.5 cM with a known 2nd cousin. So, it sounds like your relationship with the adoptee you discuss above is 2nd cousin or perhaps 2nd cousin, once removed.

Assuming it's a 2nd cousin relationship, this means that you and the adoptee share one set of great-grandparents. Unless you have some clues to narrow it down, it could be any one of the four sets of great-grandparents in your tree and any one of the four sets of great-grandparents in his tree.

I've bolded the questions you're asking.

The first question is if your brother and the adoptee share the same paternal line. That's possible, but you wouldn't know unless they show up in each others' match list at FTDNA. If they share the same great-grandfather in the paternal line, they should show up as close matches at the 37 (GD of 2 or less) and 67 (GD of 4 or less) marker levels. Have you checked your brother's yDNA match list to see if the adoptee is there at the 37 or 67 marker level? If the adoptee doesn't show up there, then they almost certainly don't share the same paternal line. That would indicate that the common great-grandparents probably aren't your paternal grandfather's father or his paternal grandfather's father.

Your second question is about further yDNA testing of your brother to rule in or out that the adoptee is related to you through the paternal line. That's one way to narrow down that possibility. If your brother were to order the R1b-M343 Backbone SNP pack, it would tell him whether his paternal line is also L48+. If your brother turned out to be L48-, that would rule out that he and the adoptee are in the same paternal line. If your brother is L48+, that would not be definitive, because that's a fairly common haplogroup and wouldn't necessarily mean that your brother and the adoptee share a recent common paternal line ancestor. As I mentioned in answering the first question, if your brother and the adoptee share the same paternal line great-grandfather, the adoptee should show up in your brother's 37 and 67 marker matches. That would be definitive. So, you should be able to tell if that's the common line without having your brother do the SNP testing.

[Hollis]

Thank you so much MMaddi,
I appreciate your taking the time to explain so thoroughly. Yes, the adoptee is my about second cousin. The adoptee has not had a test on FTDNA so he is not on any Y matches of my brother's! I think he tested at 23 and me, and I have not tested there. I will suggest he take the Y test at FTDNA. 67 markers. Not only do I have a brother with the Y test, I also have a first cousin male with a Y test on FTDNA. Both are RM269.
The adoptee understands less than I do about DNA testing. I asked him to send the list of markers and values that came with his Y test, but he doesn't know where to find them. I think whether I have the answer for him (and I may with a tree of 7700, or someone else will show up as a match to him on the Y, FTDNA is the place he is more likely to find an answer for the male line. Thank you again for your time.
Susan Hollis

[MMaddi]

Originally Posted by Hollis

The adoptee understands less than I do about DNA testing. I asked him to send the list of markers and values that came with his Y test, but he doesn't know where to find them.

23andMe only tests SNPs, so we won't find any STRs in his results. He can upload his 23andMe raw data into the FTDNA database for free. That will set up an account here for him. Then he can order STRs - 67 is the recommended number to order. FTDNA will send him a test kit so that he can submit a DNA sample that they can test.

[Hollis]

MMaddi, he and I thank you. I did not know they tested differently. He needs to do a FTDNA 67 test. He thinks I need to upgrade my brother's Y67 test. I am determined to be patient and help him any way I can. I do understand we must match on the STR test, but he does not as yet. I will be patient. Thank you again...you are most kind. Susan Hollis
Littleton, Colorado

[David R McMahon]

I know even less about the genetic groups but I was tested on 23and Me and I am part of that same Heplogroup and sub-group. I am also looking for the father of my grandfather. He would have been traveling in SouthEast Ohio in the early 1900's.
I hope that adds some pieces to the puzzle.