GENEALOGY-DNA-L ArchivesArchiver > GENEALOGY-DNA > 2009-08 > 1251091379
Subject: Re: [DNA] Expected autosomal block sizes
Date: Mon, 24 Aug 2009 01:22:59 EDT
>To be clearer, as between myself and my first cousins, our fathers
>were 1st cousins (sons of two brothers), and our mothers were sisters.
>I'm wondering if I should expect to learn anything useful from their
>X chromosomes by testing them at 23andme.
Well, the sons of brothers won't contribute anything to your
X chromosome except for the tips. But if you have a male first
cousin, he will be more like a brother in the inheritance of the sex
chromosomes (X and Y) only. Each mother will scramble
her two X chromosomes before passing one on to her
offspring. You should each get the same Y chromosome.