Tracking migrations with molecules

[Patrick Foley]

Dear Leppers,

To address more precisely the claim that butterfly releases won't mess up
biogeographic studies, consider the strengths and weaknesses of one suggested
loophole.

Paul Cherubini wrote

> Earlier this year geneticist Bruce Walsh explained why even massive
> transfers would not confound these types of studies: Bruce wrote:
>
> " However, human geneticists
> have developed methods based on tightly linked markers (STRs
> [simple trandem arrays] linked to SNPs [single nucleotide
> polymorphisms] ) that allow the age of migration events to be
> ascertained.  These approaches have been used to distinguish recent
> from historical human migrations. .."

STR probably stands here for short tandem repeats. You might want to look at
Tishkoff et al. 1996 Science 271:1380-1387. In which human exodus from Africa
is nailed down to 102.000 to 450,000  years ago using a short tandem repeat
"locus" on chromosome 12. This result shows the power and precision of such
techniques.

Patrick Foley
patfoley at csus.edu