GENEALOGY-DNA-L ArchivesArchiver > GENEALOGY-DNA > 2005-06 > 1118457352
Subject: Re: [DNA] High Mutation Rate in Second Cousins
Date: Fri, 10 Jun 2005 22:35:52 EDT
I think Dale is right on target here. You're seeing fast mutators (on
average) mutating in a few generations in your paternal line. In the Liles family
project, 570 can be used to distinguish 3rd cousins. In my Humphrey line CDYa
& 442 distinguish 3rd cousins.
In a sense we're lucky: we don't need a super-fast mutator to distinguish
finer lines (yet).
Because of the (theroetical) possibility of parallel or even back-mutations
in my 11-generation paper trail, I included an alternative calculation for
mutations from our ancestral haplotype & associated rate in Charles's YSTR
Blog. And calculated theoretical error intervals.
In a message dated 6/10/2005 6:04:43 PM Pacific Standard Time,
Recall the ol' bell-shaped curve. Consider sampling. Remember that
someone has to represent the outriders of reality - as we find such to
exist. You and the rest of your Faux relatives represent the 99.99th
percentile of the presently known collection of those who've undergone
DNA testing in terms of internal divergence. Y'all are the statistical
And above all - chance rules - even in genetics!
So, you and your relatives have established a new level of diversity of
mutation within a single, documented lineage! Nothing more, nothing less.
David Faux wrote:
>I received the last panel of 13 markers from FTDNA today and the results
were quite dramatic.
>Previously my Dad's second cousin, "RF" (MRCA born 1814) and he matched
only 23/25. All 13 markers of the second panel match and there are no matches
at even 22/25 except with other Fauxes. The R1b signature is very rare at
that level of resolution.
>Now the match drops to 32/37. What is very strange is that a distant
cousin, "IF" (MRCA bon 1618) also mismatches both of us on 3 of the four markers.
What is it about those four markers and the Faux family?
>Here are the results:
>DYS390 = 25 DF; 24 RF; 24 IF
>DYS439 = 12 DF; 13 RF; 14 IF
>DYS576 = 17 DF; 18 RF; 16 IF
>DYS570 = 17 DF; 19 RF; 18 IF
>The paper trail is without question and as I said the signature is rare
enough that there are no others except Fauxes in 18,000 that match even 22/25.
>Anyone have any ideas why these four markers, especially the last three
where all parties differ, should be consistent mutators - chance factors? I may
have the dubious record of having the largest number of mutations per
transmission yet known in a fully documented family. I guess I need to have my
Dad tested for the last 13 markers in case he and I differ.
>Any notions of what is going on?
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multi-family project:Humphrey, Liles, Morton