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Archiver > GENEALOGY-DNA > 2004-01 > 1074141776


From: Andrew Bond <>
Subject: Re: [DNA] Butler's talk at NIST
Date: Wed, 14 Jan 2004 20:43:03 -0800 (PST)
In-Reply-To: <40060E0B.7060206@comcast.net>


Bonnie Schrack <> wrote:Last message of the night (I hope!):

My dad reports that the talk was very interesting, Butler is a fun and
entertaining speaker.

He discussed his involvement in identification of the victims of the
destruction of the World Trade Center, using the tiny fragments picked
out of the debris. (I guess when you do a lot of grim work, you need to
find things to laugh about.) They used STRs, and not only from the Y
chromosome. They got many samples from family members, but also were
able to extract DNA from missing family members from personal items such
as toothbrushes.

The piece of information my dad found especially interesting is that 28%
of the victims identified did not match the DNA of their putative
fathers. In these cases, they never disclosed this to the surviving
father, but did mention it confidentially to the mothers!

The other thing from the lecture he remembered to tell me about, was
that at crime scenes, anyone who owns a cat usually leaves behind cat
hairs! I can well imagine! I'm constantly covered with hairs from my
cat Hans, whose longish, white hairs just make a mess of my black winter
clothes and coat. (My other cat, Istvan's, hairs aren't so bad, as
they're short and black.) . . . So Butler worked on a project to study
the DNA of domestic cats. ( I saw that article mentioned somewhere when
I didn't have time to download it.) Turns out, they didn't do it just
for fun, but for this practical, forensic purpose. Well, I'll be....


As far as the 28%, that seems very high. Although at a genetics conference I heard from a colleague that he has found (while studying the genetics of a certain disorder) that some pairs of dizygotic twins have different fathers. They keep that information confidential so the "father" and twins never find out (unless they suddenly become interested in starting a Y DNA study for genealogy :-).


The forensic analysis of pet DNA has been used as a technique for a few years now. There is even this paper that came out in 1999 that used mtDNA analysis of a dog. The funny thing is the dog was the accused.
Forensic mtDNA hair analysis excludes a dog from having caused a traffic accident.

Schneider PM, Seo Y, Rittner C.

Institute of Legal Medicine, Johannes Gutenberg University, Am Pulverturm 3, D-55131 Mainz, Germany.

A dog was suspected of having caused a traffic accident. Three hair fragments were recovered from the damaged car and subjected to DNA sequence analysis of the canine mitochondrial D-loop control region. The results were compared to saliva and hair samples from the alleged dog, as well as to control hair samples from four unrelated dogs of different breeds. Two sequence types exhibiting five nucleotide differences in a 377 bp fragment were identified among the four controls. Whereas the evidence hair fragment was identical to the type 1 control sequence, the alleged dog shared the type 2 control sequence except for one position. Thus the dog could be excluded as the origin of the hair fragment. As canine mtDNA appears to exhibit only limited polymorphism, mitochondrial D-loop sequence comparison is currently only suitable for exclusions.

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