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Zachriel



Posts: 2595
Joined: Sep. 2006

(Permalink) Posted: Mar. 21 2007,06:41   

PaV            
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Where is the data?  

This is why most people can't sustain a line of argument with IDers. IDers forget so easily that you have to continually restart the argument. The data PaV is requesting is in the very case study under discussion, along with a variety of other cites that have been provided. Suggestion, hypothesis, prediction, data, confirmation, insight.  
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In 1949, J. B. S. Haldane suggested that the reason that the deleterious S allele occurs in high frequency in some human populations is because individuals who are heterozygous for the allele (genotype AS) do not suffer from the severe anemia due to cell sickling, but also enjoy some resistance to malaria. He based this proposition solely on the observation of higher than expected frequencies of allele S in regions where malaria is endemic.

PaV            
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Now, I don’t consider this NS, but simple stochastic genetic behavior. What we have is a “defective” hemoglobin molecule that has, as an unintended consequence, some remedial effect in the case of malaria.  

Gee whiz. The allele frequency can be shown to have changed over generations in response to the environment. This isn't "NS" because, well, PaV doesn't want it to be, or can't allow it to be admitted.

PaV            
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 If, indeed, this were NS at work, then in malaria free areas, over the long run, this allele should vanish—IOW, NS would “punish” it. But you see, this study strongly suggests this isn’t the case.

The timeframe is only a few generations. As sickle cell trait is recessive and not always lethal when homozygous, it would be expected to decrease in frequency, but not necessarily disappear.

PaV            
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The Hardy-Weinberg Law seems to be taking over.

Hardy-Weinberg assumes the absence of selection, certainly not the case with populations currently harboring the trait. Sickle cell is a significant parenting issue among descendents of the African Diaspora.

Don't forget to let us know how your research in support of your "hypothesis" works out. And don't forget your pills!

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Tard Acquisition and Repository Department

   
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