Y-DNA Test Turned up a Perfect Match with Different Last Name

[TunjiLees]

Hi Laura,  a GD level 1 match at Y-37 is going to be a long time in the past, at least 1,000 years ago.  At that age range, an autosomal test will not find any link either.   Based on what I have learnt, to be brutally honest a Y37 test is never going to show you very much at all if you are looking for actual close relatives, it will only give a basic picture of the migration line for your family.

Richard

Hi everyone,

I'm still learning about Y-DNA so correct me if I'm wrong but I don't think what rsel is saying is accurate. Let me explain why.

I have one close Y-DNA match with a genetic distance of 3 at Y37.

According to FamilyTreeDNA's TiP Report, my match and I have a 71.79% chance of being related within the last 8 generations.

Through paper records, I know that we don't have a common ancestor within the past 5 generations. When I supply that fact to the TiP Report, I then get a revised estimate of there being a 58.85% chance of sharing a common ancestor within the last 8 generations.

Let's say a generation is 30 years. 8 generations x 30 years = 240 years ago

That is with a genetic distance of 3.

A genetic distance of 1 shouldn't be 1,000 years ago, but much closer to the present.

[rsel]

Hi everyone,

I'm still learning about Y-DNA so correct me if I'm wrong but I don't think what rsel is saying is accurate. Let me explain why.

I have one close Y-DNA match with a genetic distance of 3 at Y37.

According to FamilyTreeDNA's TiP Report, my match and I have a 71.79% chance of being related within the last 8 generations.

Through paper records, I know that we don't have a common ancestor within the past 5 generations. When I supply that fact to the TiP Report, I then get a revised estimate of there being a 58.85% chance of sharing a common ancestor within the last 8 generations.

Let's say a generation is 30 years. 8 generations x 30 years = 240 years ago

That is with a genetic distance of 3.

A genetic distance of 1 shouldn't be 1,000 years ago, but much closer to the present.

Hi, if you go onto the forums on FTDNA, where there are folks who know a lot more about this than I do provide lots of good information, they will always tell you don't take much notice of Y3 matches.   Whilst they can be close, they can also be a long time ago, you just don't have the detail to know anything for sure.   

Richard

[TunjiLees]

This is taken directly from the FTDNA website for Y-37 matches at a Genetic Distance of 1;

Genetic Distance: 1
Relationship: Tightly Related
Interpretation: A 36/37 match between two men who share a common surname (or variant) indicates a close genealogical match. Very few people achieve this close level of a match, and it is within the range of most well-established surname lineages in Western Europe. It’s most likely that they matched 24/25 or 25/25 on a previous Y-DNA test, and the mismatch will be found within DYS576, DYS570, or CDY.

https://learn.familytreedna.com/y-dna-testing/y-str/two-men-share-surname-genetic-distance-37-y-chromosome-str-markers-interpreted/

If there is not a matching surname then that likely indicates a NPE (non paternity event) or adoption on one of the lines.