This may seem like a silly question, but I need to know how to count SNPs.

I am comparing my results with those of my closest STR match, same surname, 103/111.

He and I share 93 novel variants and have no differing known SNPs.

There are 7 SNPs for which he has the ancestral value and I have the derived.

There are 7 different SNPs for which I have the ancestral value and he has the derived.

So for purposes of estimating the TMRCA do I use 7 or 14 SNP differences?

Thanks for any insights.

Jim

I am comparing my results with those of my closest STR match, same surname, 103/111.

He and I share 93 novel variants and have no differing known SNPs.

There are 7 SNPs for which he has the ancestral value and I have the derived.

There are 7 different SNPs for which I have the ancestral value and he has the derived.

So for purposes of estimating the TMRCA do I use 7 or 14 SNP differences?

Thanks for any insights.

Jim

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