> BTW, why some diseases are more prevalent in some races
> or cultures and not in others? I remember that my wife told
> me about a child disease that "usually" has more
> complications when the infected is "black".
>Some diseases are the result of the presence of a specific gene or suite of genes in
>a population. Tay Saxhs is a disease confined mostly to polish jews. Sickle Cell
>Anemia is a disease seen almost exclusively in africans and Thalasemia seen mostly in
>southern europeans. What is interesting is that some of these genetic disorders
>persist. it has now become clear that some (or maybe most) of these "defects" confere
>some advantage on those who carry them. For instance, Sickle Cell gene produces
>sickle cell anemia when present in both genes (homozygous). When present in only one
>of the two genes (heterozygous) it provides its carrier with relative protection from
>malaria. So in parts of the world where malaria is endemic this mutation will tend to
>persist. Blood groups seem to have the same effect. Some blood types (O I beleive)
>protect against one of the bacterial diarrhea syndromes (cholera?). In American
>Indians this blood type did not exist because the bacteria did not come !
!
to the new world until brought by
europeans. So american indians were particularly sensitive to this infection.
As Jarod Diamond pointed out in "Guns Germs and Steel" the europeans wiped much of the
native american population without raising a hand. European endemic diseases (the
diseases of crowding) such as small pox spread through the native american population
like acid.
