Re: Mitochondrial Eve

Biochmborg@aol.com
Fri, 21 May 1999 15:26:18 EDT

In a message dated 5/21/99 11:52:33 AM Mountain Daylight Time,
ssclark@facstaff.wisc.edu writes:

>
> I did claim your arguments were circular.
>

Ah, so you did; my mistake. I didn't see the rest of your comments because
it looked like you had stopped commenting when the repeat of my message
appeared. I'll have to look at them to see what else you said. Sorry for
miscomprehension.

>
> Also, the definition of an
> allele has nothing to do with "true" genes. This is basic genetics.
>

That depends upon whether you talk to a geneticist, a molecular biologist or
someone trained in both fields. A geneticist still uses the term the way it
was used before genes were linked to DNA, namely as those genes that
determine the different forms of the same trait. In that sense, alleles
refer only to true genes. A molecular biologist uses the term as it was used
after genes were linked to DNA, namely as DNA sequences that differ by one or
more substitutions. In that sense, alleles can refer to any variation in
nucleotide sequences, as you pointed out with microsatellites. A molecular
geneticist uses the term both ways interchangeably, sometimes simultaneously.
Both usages are appropriate, as long as the context is clearly spelled out.

Kevin L. O'Brien