GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2006-12 > 1165003888


From: (John Chandler)
Subject: Re: [DNA] Question on testing for y haplogroups
Date: Fri, 1 Dec 2006 15:11:28 -0500 (EST)
References: <120120061710.13420.45706206000782870000346C220073483002019B970E9F030B9D0E080C079D@comcast.net>
In-Reply-To: <120120061710.13420.45706206000782870000346C220073483002019B970E9F030B9D0E080C079D@comcast.net>(richardmpayton@comcast.net)


Richard wrote:
> For our haplogroup I members (predicted) their haplogroup prediction
> from Family Tree DNA based on 12 STRs is only "I"; I presume this is
> either because the Family Tree DNA database includes 12 marker STR
> matches for more than one haplogroup I subclade, or (more likely),
> no exact 12 marker match has been SNP tested.

As Ken remarked, FTDNA hasn't gone as deeply into haplogroup I as
one might have hoped. The problem, however, is in the limited
SNP testing done on the reference samples in the FTDNA haplogroup
database -- many of those samples were never tested for subclades
of I. The FTDNA prediction algorithm can't go any deeper than
the testing of the reference samples, and so "I" is often the
prediction, even when more is evident from the haplotype.

John Chandler

This thread: