GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2011-08 > 1314552030


From: Dienekes Pontikos <>
Subject: Re: [DNA] The peopling of Europe and the cautionarytaleofYchromosome lineage R-M269
Date: Sun, 28 Aug 2011 20:20:30 +0300
References: <B8CAFFA925E34BC99751E6E13CFCAA31@PC><CAKWx04TCOymg=jW1-y8_nNmwpCH8HSoi+nLdUDsB+OwDt64zsg@mail.gmail.com><001f01cc65a3$c111ddf0$433599d0$@net>
In-Reply-To: <001f01cc65a3$c111ddf0$433599d0$@net>


On Sun, Aug 28, 2011 at 7:58 PM, Tim Janzen <> wrote:
> Dear Mike,
>        I agree that using the SNP counting method along with STR variance
> is a very good approach, particularly for looking at the age of older
> subclades.  The main problem with the SNP counting method is that we still
> don't have a highly accurate age for Y Adam so that we can root the Y tree
> appropriately.

We don't need an age for Y Adam, because we can measure the mutation
rate directly; we don't have to calibrate it based on assumptions
about the date of Y Adam.

That is how Cruciani et al. estimated the age of the root of the
Y-chromosome phylogeny.

http://dienekes.blogspot.com/2011/05/father-of-us-all-142-thousand-years-ago.html

And, our knowledge of the Y-chromosome point mutation rate is only
going to get better as it becomes practical to fully sequence the
Y-chromosomes in an ever-increasing number of father-son pairs, or
deep-rooted pedigrees

http://dienekes.blogspot.com/2009/08/human-y-chromosome-mutation-rate.html

Genealogists may actually prove to be quite useful here, since two
living men who are descended from two sons of a man who lived
centuries ago are separated by a known number of generations, and
fully sequencing their Y-chromosomes gives a much better estimate of
the mutation rate than can be achieved from a single father-son pair.
For the same cost you get the equivalent of dozens of father-son
pairs.

So, it's a good idea for genealogists and historians to identify
genealogies of this sort in preparation for the inevitable
availability of reasonably-priced full-Y sequencing.

--
Dienekes' Anthropology Blog: http://dienekes.blogspot.com
Dodecad Ancestry Project: http://dodecad.blogspot.com

This thread: