[extropy-chat] Training the immune system

[The Avantguardian]

--- "J. Andrew Rogers" <andrew at ceruleansystems.com>
wrote:
> Again, the more interesting question to me is why
> the Europeans  
> appear to have collected so many disease resistance
> mutations  
> relative to other genomes, and from what I have read
> and heard from  
> researchers there is a noticeable difference in the
> number of  
> resistance markers in European populations versus
> others.  

Two important factors in answering your question are
genetic diversity and cities. Europeans had been
interbreeding with peoples from all over the Eurasian
land mass for millenia. They therefore had much more
diversity in disease resistance genes at their
disposal.

They also lived in crowded cities that were breeding
grounds for epidemics, thus those disease resistance
genes were constantly being selected for and
reinforced in the population.

The Native Americans, on the other hand, were less
genetically diverse because of the genetic bottle-neck
caused by the immigration of the original settlers
during the last ice age over the bering-strait land
bridge. After the ice age ended, they were genetically
isolated and so their only disease resistance genes
were the ones brought over by the relative handful of
originals settlers, BEFORE the advent of cities.

The Native Americans also kept their land sparsely
populated. This low population density combined with
isolation prevented routine epidemics selecting for a
wide array of disease resistance genes.

 


Stuart LaForge
alt email: stuart"AT"ucla.edu

"What I am going to tell you about is what we teach our physics students in the third or fourth year of graduate school... It is my task to convince you not to turn away because you don't understand it. You see my physics students don't understand it... That is because I don't understand it. Nobody does." - Richard Feynman on QM

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