mendelian genetics

[Alex Boyd]

No: HPFGUIDX 123710


<snip of me talking about genetics>

> Antosha:
> 
> You know, Celaria (I don't know if she's on HPfGU) pointed out to a
few of us that, if the 'W' 
> gene is truly dominant, (and if there is just one gene) then there
could be no such thing as 
> Muggle-born magic-users, since, if the gene was present in either
parent, the trait would 
> have manifested.

D'oh!  Yeah, you're right--and the fic sounds good, I'll have to look
for it. What I perhaps should have said--given that the main point of
my post was that magic probably wasn't governed by a single gene--is
that it takes more M genes to cancel out a W gene than it takes W
genes to cancel out an M.  or something like that.  

I'm thinking of how having 6 digits is a dominant trait--if your
parents have it, you're almost always going to have it (in cats, and
I'm pretty sure in humans too)--but it can also somehow be hidden in
the phenotype for a while but still exist in the genotype, so it can
skip generations without spontaneous mutation to recreate it every
time.  I'm not sure how the actual mechanism works, but it does work,
with the 6-finger trait, so it's plausible that magic could be the
same way.  

Alex, who really knows far less about genetics than I should if I'm
going to weigh in on this thread