September 08, 2015

IQ differences between populations are genetic

Knowledge of the genes associated with IQ has now advanced considerably.  As everyone in the field expected, IQ is governed not by one gene but many.  It is polygenetic.  This is in accordance with the view that IQ is just one aspect of general  biological good functioning.  The brain is just another organ of the body and if the body as a whole is functioning well, the brain should usually be pretty good too.

The researcher below selected 9 alleles that seemed particularly influential on IQ and combined them to get a score which could be called the genetic IQ score.  He calls it a metagene.  He found that the score varied widely between populations but that it correlated extremely strongly with IQ as measured by IQ tests.  Nations that averaged out high on IQ as measured by conventional IQ tests also had a lot of people with high genetic IQ scores.

So much for the common Leftist claim that IQ is only what IQ tests measure.  What IQ tests measure is in fact closely related to brain genes.  You could in theory examine an individual  person's brain and get an accurate IQ score that way  -- without using a conventional IQ test.  It has not got to that point yet.  Only whole populations have been examined so far -- but the future is now in plain sight.  IQ tests may some time in the not distant future be replaceable by genetic examinations.

Leftists have always argued that genetic determination of IQ within a population does not mean that between-population differences are also genetically determined.  That is of course logically true but highly improbable.  That claim would now appear  to have been examined and found wanting.

The implication, of course is that the black IQ deficit is also a function of black genes but anybody who tried to test that directly would probably be lucky to escape with his life.  So we just have to remind Leftists that blacks are people too and that what is true of people worldwide must also therefore be taken as true of blacks.  Blacks just don't normally have the genes needed for high IQ.

That is what the science shows. When Warmists talk about "The Science", they never actually mention any. Good reason: What they call "science" is in fact prophecy. See below for some real science:

A review of intelligence GWAS hits: Their relationship to country IQ and the issue of spatial autocorrelation

By Davide Piffer, Ulster Institute for Social Research, London, UK

Abstract

Published Genome Wide Association Studies (GWAS), reporting the presence of alleles exhibiting significant and replicable associations with IQ, are reviewed. The average between-population frequency (polygenic score) of nine alleles positively and significantly associated with intelligence is strongly correlated to country-level IQ (r = .91). Factor analysis of allele frequencies furthermore identified a metagene with a similar correlation to country IQ (r = .86). The majority of the alleles (seven out of nine) loaded positively on this metagene. Allele frequencies varied by continent in a way that corresponds with observed population differences in average phenotypic intelligence. Average allele frequencies for intelligence GWAS hits exhibited higher inter-population variability than random SNPs matched to the GWAS hits or GWAS hits for height. This indicates stronger directional polygenic selection for intelligence relative to height. Random sets of SNPs and Fst distances were employed to deal with the issue of autocorrelation due to population structure. GWAS hits were much stronger predictors of IQ than random SNPs. Regressing IQ on Fst distances did not significantly alter the results nonetheless it demonstrated that, whilst population structure due to genetic drift and migrations is indeed related to IQ differences between populations, the GWAS hit frequencies are independent predictors of aggregate IQ differences.

SOURCE

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