samedi 2 avril 2016

If Anyone THought CMI WAS Admitting Beneficial Mutations

... that person must have BOTH missed what date it was yesterday AND missed clicking the link.

I didn't lie.

I asked whether, and did not claim that they were admitting them, and Alex Williams did write about them - namely about them conspicuously missing in the medical and genetic literature about human mutations. Here is link again, but with full title:

CMI : Beneficial mutations: real or imaginary?—part 1
Alex Williams


Human genome studies are being carried out all around the world at present and the major findings can be summarized in just a few words: accumulating mutation load and a multitude of associations between mutations and diseases. The Human Gene Mutation Database11 currently contains records of more than 141,000 mutations. New ones are being discovered at a rate of over 11,000 per year. A September 2012 summary reported that of these about 6,000 constitute ‘disease associated’ and ‘functional’ polymorphisms (different versions of a DNA sequence).12 Notice that the classification recognizes just two categories—mutations are either ‘disease associated’ or they are ‘functional’. There is no category labelled ‘beneficial’.

I take this to mean that of 141,000 mutations, known from genetics only, 6000 have been looked at for their specific phenotypal effect and they divide into disease associated and functional.

I also take it that "functional" does not mean "more functional than previously", but "as functional as previously" (though perhaps with a slight twist).

Beneficient mutations would mean "more functional than previously" (absolutely and not just for a certain environment).

Now, more melanine is more functional for those living near equator since protecting from bad sunrays. Less melanine is more functional for those living nearer but not too near poles, since they have less sunshine to synthesise vitamin D from and need more of it to get under the skin.

But NEITHER mutation (or chromosomal rearrangement, don't know which) is per se "more functional", as it would be "more functional" suddenly to have a gene for language.

See article The FOXP2 gene supports Neandertals being fully human
by Peer Terborg and Royal Truman

Two indications are given about differences in that sequence.

However, some people are born with an impaired ability for language and speech development, a syndrome known as specific language impairment (SLI). Children with SLI lag behind their peers in language development and comprehension, which contributes to learning and reading disabilities in school. Recently, a defective gene in a three-generation family that had the SLI speech disorder was identified as the FOXP2 gene. The FOXP2 gene was also defective in a non-relative who suffered from the same disorder. Those with a defective FOXP2 are more prone to display SLI difficulties, but the same mutational variants do not always result in this disorder, reflecting the complexity of the genetics of speech.

So, one or more not specified deviations from normal human FOXP2 gene is a disease associated mutation.

But there is also a difference with similar or "correspondent" gene in non-rational animals:

In contrast to these five sequences, the human version differs at two positions. Depicted in figure 1, amino acid residue 304 has ‘N’ for humans, ‘T’ for the other five organisms; amino acid residue 326 has ‘S’ for humans, ‘N’ for the other five organism.

And as article will tell you, Neanderthal men had 304 N and not T, 326 S and not N.

So, we see in medical literature a mutation or more which makes FOXP2 gene less functional but no mutation has shown it to become more functional.

Supposing the two loci 304 N and 326 S were making it function in a human way, that would mean that TWO mutations were needed to get there.

Each of them useless without the other.

There is more to it.

Those with a defective FOXP2 are more prone to display SLI difficulties, but the same mutational variants do not always result in this disorder, reflecting the complexity of the genetics of speech.

In other words FOXP2 gene in human shape is NOT enough. Either there is some other gene too OR (which we know for philosophical rather than medicval reasons anyway) the human mind is a substance over and above our genome and it sometimes overrides defects in the FOXP2 gene.

Hans Georg Lundahl
Nanterre University Library
Saturday of Easter Week

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