I concurr with Odile.
It really sounds surprising that you get nuclear but no mtDNA from
teeth.
As to the preparation of teeth for DNA extraction, I would recommend
only usng the root part which contains DNA, grind that and use 0.1 to
0.3g for an extraction. This way you only extract from the DNA
containing material and - as a plus in the conservation sense - keep the
crown part intact which might be of interest when working with
historical specimen.
Even when only using the dentin/root part, you might get lower DNA yield
than with the same amount of bone, but the DNA should be more intact.
Though I predominantly work with nuclear DNA, I don't see any reason why
the same should not be true for the mtDNA.
Maybe it would be worthwhile to try mtDNA mini-primer sets that break up
HVI and Hvi in sub-sections...
Regards,
Wera
Wera M Schmerer Dr rer nat, Dipl Biol
University of Wolverhampton
School of Applied Sciences
Forensic and Molecular Science
Wulfruna St
Wolverhampton, WV1 1SB
[log in to unmask]
-----Original Message-----
From: Ancient DNA List [mailto:[log in to unmask]] On Behalf Of
Loreille, Odile CONTR
Sent: 06 July 2009 15:45
To: [log in to unmask]
Subject: Re: mtDNA in teeth (UNCLASSIFIED)
Classification: UNCLASSIFIED
Caveats: NONE
Our mtDNA casework section gets great results with teeth. They actually
often work better than bones.
What extraction protocol are you using? I'd think that if you grind a
complete tooth, the weight you'll get from a tooth will be a mixture of
dentin and enamel (that contains no DNA). 200mg of this powder would be
very different than 200g of bone.
Two: I am somehow surprised to read that you get nuclear DNA form teeth
but no mito. Our experience is that when STR work, then mito
amplifications will always rock. You just need to target the right
amplicon size. How big are your mt amplicons?
Hope this helps,
Odile
Odile Loreille
Armed Forces DNA Identification laboratory USA
-----Original Message-----
From: Ancient DNA List [mailto:[log in to unmask]] On Behalf Of
Eveline Altena
Sent: Monday, July 06, 2009 6:24 AM
To: [log in to unmask]
Subject: mtDNA in teeth
Dear colleagues,
At our lab we have the idea from experiences with both forensic and
archeological human samples that there is much less mtDNA present in
teeth then in bone. We think so because sometimes we can get nuclear DNA
from teeth but no mtDNA (or we get mtDNA from bones but no nuclear DNA).
Even though we use very sensitive multiplex PCR kits for forensic cases
(eg Powerplex16 form Promega).
I have heard from two other labs that they have the same experiences,
but I am not aware of articles that have tested this or where this is
discussed. Does anyone know of such an article or does anyone have the
same experiences?
Best regards,
Eveline Altena
PhD student ancient human DNA research
Forensic Laboratory for DNA Research
Leiden University Medical Center
PO Box 9600
2300 RC Leiden
The Netherlands
phone: +31 (0)71 526 9540
fax: +31 (0)71 526 8278
Classification: UNCLASSIFIED
Caveats: NONE
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