Wizen recessive gene/Petunia

[sbursztynski]

No: HPFGUIDX 80312

---> 
> In the WW, exclusive intra-marriage would have eventually lead to 
> serious inbreeding, with all the negative health effects attendant 
to 
> that problem.  Over time, the problem would tend to accelerate the 
> demise of the community; as the number of viable mates declines, 
> inbreeding becomes more difficult to avoid, until it is 
unavoidable, 
> and the population would then likely collapse in just a few 
> generations.
> 
> 
> Richard

It seems to me that there *was* a serious case of inbreeding among 
the "pureblood" families (perhaps why there seem to be so many 
nutters among them?). The way I see it is, there were a lot of 
wizards who went "underground" to avoid persecution and married out. 
And then, generations later, the recessive gene springs up (my 
biology is only high school, but I think this would work). This is 
why magical kids turn up in otherwise Muggle families.

Just an idea.

Sue B