GENEALOGY-DNA-L ArchivesArchiver > GENEALOGY-DNA > 2010-03 > 1268627194
From: "Ken Nordtvedt" <>
Subject: Re: [DNA] Clades, Definitions, Discoveries, FTDNA
Date: Sun, 14 Mar 2010 22:26:38 -0600
----- Original Message -----
From: "Steven Bird" <>
> 1 X 10-9 is not "my number"; it is quoted from Hartwell "Genetics";
> McGraw-Hill (2008), p. 396, ISBN #9780072848464. That is the mutation
> rate for the entire genome, which consists of 3 billion base pairs. If
> every male on the planet had a child at the same time, then your argument
> would hold. However, half of the offspring would be girls. And of
> course, not all of the boys will have offspring.
I granted you your one in a billion for the sake of argument? What do you
want? I think you'll find the y snp mutation rate in the 25 million sites
generally considered useful to be order of magnitude higher. But we are not
here debating a factor of 10 in how many times any y nucleotide site mutates
in the y tree back to genetic Adam. That's chump change.
I talked over a generation, not at the same time, and I threw away the 3 in
3 billion and the boy/girl split. As each generation passes, there better
be about one male produced for the next generation for each male in the past
generation, or the population shrinks away.
Do you really still reject the approximate conclusion; that each generation,
each and every one of the 25 million y snp sites mutates about once or
more --- of course some sites more and some less than average. ?
We could do a careful estimate of how many father/son transitions there are
in the total y tree back to genetic Adam. And I assure you it will be many
billion. So if the probability that a snp site to mutate each father/son
transition is YOUR one in a billion, that means that site mutates many times
at different places in the y tree.