Milk Gene

[David Huen]

In article <Pine.3.05.9412200728.A21868-c100000 at mcz>, dmw at MCZ.HARVARD.EDU
(Daniel Weinreich) wrote:

> I would only add that the "polarity" of the change may be the reverse of
> that suggested in the excerpt (as implied by the original post, in which
> lactose tolerance in adults was described as "a genetic defect").  It
> seems plausable that the "ancestral state" in humans was lactose
> intolerance, since dairy farming is a relatively recent innovation.  Can
> adult chimps digest milk?  I bet they can't. 
> 
> Speaking as a descendent of dead white european males, I too first
> conceptualized lactose intolerance as a genetic "loss", as do the authors
> of the above excerpt, but that may not be the biological reality. 
> 
And as a lactose-intolerant Oriental, I wonder why lactose is so uniquely a
component of milk? Is there a milk (excluding soy of course :-) that
doesn't have lactose as its carbohydrate? It would seem strange that in the
process of developing lactation, one actually also developed the synthesis
of a sugar not used elsewhere. Is lactose synthesised for any other purpose
in vivo?