Re: Why so few matches? #dna

Arline and Sidney Sachs
 

To answer Cindy g question "Why so few matches?, the first thing when
working with the Y-DNA is most males' mutations are lost because they have
no males on their direct paternal line. All males and females are from
the same two persons, one male and one female, that lived most likely at
different times. They were not the only people living then, therefore all
of others had their direct lines died out. For example, if one third of
the males have no sons, than only half of them will have grandsons by
their paternal line. As an example, my grandfather had seven sons. They
have only 5 sons. >from them, I was the only one with sons, 3 of them.
from them I only have one grandson. If he does not have any, the paternal
line will be gone.

Secondly the Y-DNA testing used STRs to find matches. Almost all the
mutations on them are the kind that a STR either lose or gain one compete
repeat at a time. However, at very rare time it is not a single repeat
but a multiple repeats or even a partial repeat. Beside this there are
several other type of mutation that could happened. By looking a only a
few people it is impossible to tell what type of mutation occurred. That
the reason haplogroup projects are so useful. I have a cousin who family
history is Cohenim. He has zero matches at the 12 markers level, only 2
at genetic distance of 2 at the 25 level, and only 4 at genetic distance
of 4 at the 37 level. What happened is that on a single marker, he was
few repeats off >from that of the Cohenim Module Haplogroup. He, or his
father, grandfather, or earlier, had the mutation of multiple repeats,
thus no close matches since each repeat is counted as one genetic
distance.

Sidney Sachs
Lorton, VA, USA

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