From: {$to$}@meden.demon.co.uk   
      
   On 06/09/2025 05:12, Pro Plyd wrote:   
   >   
   > https://phys.org/news/2025-09-mutations-evolution-genome-random.html   
   >   
   > A study published in the Proceedings of the National   
   > Academy of Sciences by scientists from Israel and   
   > Ghana shows that an evolutionarily significant   
   > mutation in the human APOL1 gene arises not randomly   
   > but more frequently where it is needed to prevent   
   > disease, fundamentally challenging the notion that   
   > evolution is driven by random mutations and tying   
   > the results to a new theory that, for the first time,   
   > offers a new concept for how mutations arise.   
   > ...   
   >   
      
   The possibility of a mutation occurring can in principle depend on the   
   haplotype context. So if this a real effect, and not a statistical   
   fluke, this could be a case of preadaptation. It is also conceivable   
   that back mutation could have the effect of raising the frequency of the   
   relevant haplotype in the non-mutant population after the event, though   
   my intuition is that this effect would be too small to be detected.   
      
   The possibility of a mutation occurring can also in principle depends on   
   the alleles of DNA repair and polymerase enzymes present. This also   
   raises the possibility of pre-adaptation. As those enzymes and the   
   substrate are more or less independently assorting any hitchhiking   
   effect can be expected to be small, though my intuition says that the   
   effect is larger than for the haplotype mechanism. (There are fewer   
   generations of hitchhiking, but the independent assortment gets it into   
   the non-mutant population more effectively; I suspect that the latter   
   dominates.)   
      
   --   
   alias Ernest Major   
      
   --- SoupGate-Win32 v1.05   
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