yDNA matches not showing up in Family Finder

[prairielad]

..........

So, hypothetically, you could have a paternal line 4th cousin and he may show up, let's say, as a 65/67 yDNA match. But the chances are only 50% that he'll show up among your Family Finder matches at all, as any degree of cousin. And the odds that someone who's a more distant cousin than 4th will appear in your Family Finder match list drop even lower.

Just to add a little data on the odds in regards with my families results

My Father's paternal 1st cousin has a 64/67 match with man of same surname, who matches as a 5th cousin-Remote with 36.97 total cM, longest block 8.55cM.
edit When comparing this match to father's 1st cousin in chromosome browser, of shared sections only one segment of 1.04cM overlaps a shared location that cousin shares with my Father, Aunt and Uncle

Of my father's cousins 23 yDNA 67 marker level surname matches, only 8 have done the FF test. Of this 8, the above mentioned match is the only one that matches in FF.

This match does not match my Father, my Aunt, or my Uncle either in Family Finder.

Closest the common ancestor could be(to any of the 8), is a sibling to my Father's 2x Great Grandfather circa 1780.

[MMaddi]

Ok. To clarify. I have matches show up on y-dna and family finder results but none of these are on both lists.

5 of matches have the same surname and I can trace them all back to one common ancestor on the 1600's. 2 of these matches are brothers and one of the brothers matches me at 67 markers. The other cousins match at 37 markers. Why would these not show up at all on family finder?

The resolution of yDNA testing and an autosomal test like Family Finder are different.

One big factor is that yDNA does not recombine, except for a small part at the tip. (It can recombine with the x chromosome in that small portion.) So, the only changes that show up in testing of yDNA STRs are when a marker count goes from 11 to 12, for example, which is not due to recombination.

In the case of autosomal DNA, the 22 pairs of autosomal chromosomes undergo recombination with each generation. The mother's and father's DNA that makes up the child is a recombination of the two pairs of grandparents' DNA. A child inherits 50% of DNA from each parent, on average, and 25%, on average, from each grandparent. This goes on in each generation, meaning after several generations you don't have any measurable DNA from some ancestors.

The effect of these different types of DNA is that a 37 or 67 marker yDNA test can detect that two men are related in the paternal line over the last several hundred years, while Family Finder can only successfully detect most cousins through a common ancestor going back several generations, probably about 200 or so years. Family Finder can only reliably find cousins out to about 3rd cousins; about 50% of 4th cousins don't have enough shared DNA to be marked as cousins at all.

So, hypothetically, you could have a paternal line 4th cousin and he may show up, let's say, as a 65/67 yDNA match. But the chances are only 50% that he'll show up among your Family Finder matches at all, as any degree of cousin. And the odds that someone who's a more distant cousin than 4th will appear in your Family Finder match list drop even lower.

[arhodes]

Ok. To clarify. I have matches show up on y-dna and family finder results but none of these are on both lists.

5 of matches have the same surname and I can trace them all back to one common ancestor on the 1600's. 2 of these matches are brothers and one of the brothers matches me at 67 markers. The other cousins match at 37 markers. Why would these not show up at all on family finder?

[a shepherd]

Need some help or clarification. I have 5 very strong y37 and y67 exact matches. But none of them show up in family finder. Is this normal or not? I assumed an exact y67 match would show up as a cousin or something. Thanks for any help and advicem

Yes, it's normal. I have 3 5th to 6th cousins that match on y-dna but not on Family Finder.

[arhodes]

Need some help or clarification. I have 5 very strong y37 and y67 exact matches. But none of them show up in family finder. Is this normal or not? I assumed an exact y67 match would show up as a cousin or something. Thanks for any help and advicem