In the past 100 years since the inception of the IQ test there have been racial differences in test scores. What causes these score differences? Genetics? Environment? Both? Recently it has come out that populations do differ in allele frequencies that affect intelligence. David Piffer’s “forbidden paper on population genetics and IQ” was rejected by the new editor of the journal Intelligence. In the paper, he shows how IQ alleles vary in frequency by population. One reviewer even said it should not be put up for review, which Piffer believes there was a hidden agenda or a closed minded attitude. He even puts reviewers comments and responds to them. He says science should be transparent, which is why he’s showing the researchers’ comments on his paper.
His December, 2015 paper titled: A review of intelligence GWAS hits: Their relationship to country IQ and the issue of spatial autocorrelation shows that there are differing allele frequencies in which IQ between populations that affect IQ which are then correlated highly with average IQ by country (r=.92, factor analysis showed a correlation of .86). There was also a “positive and significant correlation between the 9 SNPs metagene and IQ”(pg. 45). However, Piffer does conclude that since the 9 alleles are present within all populations (Africans, Latin Americans, Europeans, South Asians, and East Asians) that the intelligence polymorphisms don’t appear to be race-specific, but were already present in Homo Sapiens before the migration out of Africa. He then goes on to say that it’s extremely likely that the vast majority of alleles were subject do differential selection pressure which lead increases in cognitive abilities at different rates rates in different geographical areas (pg. 49). It’s of course known that differing populations faced differing selection pressures which then lead to genotypic changes which then affected the phenotype. It’s not surprising that genes that correlate strongly with intelligence have differing frequencies in different geographical populations; it’s to be expected with what we know about evolution and natural selection. Below is the scatter plot showing the relationship between polygenic score GWAS (Genome Wide Association Studies) hits and IQ:
The fact that these differences exist should not come as a shock to those who want to seek the truth, but as seen with how David Piffer didn’t even get consideration for a revision, this shows the bias in science to studies such as this that show racial differences in intelligence exist.
Piffer’s data also corroborates Lynn and Meisenberg’s (2010) finding of a correlation of .907 with measured and estimated IQ. This shows that the differing allele frequencies affect IQ, which then affect a countries GDP, GNP, and over all quality of life.
With a sample with a huge n (over 100,000 subjects) cognitive abilities tests were performed on verbal-numerical reasoning, memory and reaction time (a huge correlate for IQ itself, see Rushton and Jensen, 2005). Davies et al (2016) discovered that there were significant genome-wide SNP based associations in 20 genomic regions, with significant gene-based regions on 46 loci!! Once we find definitive proof that intelligence differences vary between individuals, as well as the loci and genomic regions responsible, we can then move on to difference in allele frequency in depth (which Piffer 2015 was one of the starts to this project).
Moreover, genes that influence intelligence determine how well axons are encased in myelin, which is the fatty insulation that coats our axons, allowing for fast signaling to the brain. Thicker myelin also means faster nerve impulses. The researchers used HARDI to measure water diffusion in the brain. If the water diffuses rapidly in one direction, that shows the brain has very fast connections. Whereas a more broad diffusion would indicate slower signaling, thus lower intelligence. It basically gives us a picture of an individuals mental speed. Thinking of reaction time tests where Asians beat whites who beat blacks, this could possibly show how differing process times between populations manifest itself in reaction time. Since myelin is correlated with fast connections, we can make the inference that Asians have more than whites who have more than blacks, on average. The researchers also say that it’s a long time from now, but we may be able to increase intelligence by manipulating the genes responsible for myelin. This leads me to believe that there must be racial differences in myelin as well, following Rushton’s Rule of Three.
Since the mother’s IQ is the best predictor of the child’s IQ, this should really end the debate on its own. Sure on average, intelligent black mothers would birth intelligent children, but due to regression to the mean, the children would be less intelligent than the mother. JP Rushton also says that regression works in the opposite way. Both blacks and whites who fall below their racial means will have children who regress to the means of 85 and 100 respectively, showing the reality of the genetic mean in IQ between the races.
Why would differing allele frequencies lead to the same cognitive processes in the brain in genetically isolated populations? I’ve shown that brain circuits vary by IQ genes, and populations do differ in this aspect, like all other differing genotypic/phenotypic traits.
East Asians have bigger brains, as shown by MRI studies. Rushton and Rushton (2001) showed that the three races differ in IQ, brain size, and 37 different musculoskeletal traits. We know that West Africans and West African-descended people have genes for fast twitch muscle fibers (Type II) (Nielson and Christenson, 2001). Europeans and East Asians have slow twitch muscle fibers (Type I) for strength and endurance. (East Africans have this as well, which allows for ability to run for distance, which fast twitch fibers do not allow for. The same is true for slow twitch fibers and sprinting events.) Bengt Saltin showed that European distance runners have up to 90 percent slow twitch fibers (see Entine, 2000)! So are genetic IQ differentials really that hard to believe? With all of these differing variables in regards to intelligence that all point to a strong genetic cause for individual differences in other genes that lead to stark phenotypic differences between the races, is it really not plausible that populations differ in intelligence, which is largely inherited?
Is it really plausible that differing populations would be the same cognitvely? That they would have the same capacity for intelligence? Even when evolution occurred in differing climates? The races/ethnicities differ on so many different variables with differing genes being responsible for it. Would IQ genes really be out of the question? Evolution didn’t stop from the neck up. Different populations faced different selection pressures, so different human traits then evolved for better adaption in that environment. Different traits clearly developed in genetically isolated populations that had no gene flow with each other for tens of thousands of years. These differing evolutionary environments for the races put different pressures on them, selecting some for high IQ alleles and others for low IQ alleles.
We are coming to a time where intelligence differences between populations will become an irrefutable fact. With better technology to see how differing genes or sets of genes affect our mind as well as physiology, we will see that most all human differences will come down to differing allele frequencies along with differing gene expression. Following Rushton’s simple rule based on over 60 variables, East Asians will have the most high IQ alleles followed by Europeans and then blacks. The whole battery of different cognitive abilities tests that have been conducted over the past 100 years show us that there are differences, yet we haven’t been able to fully explain it by GWAS and other similar techniques. Charles Murray says within the next 5 to 10 years we will have definitive proof that IQ genes exist. After that, it’s only a matter of time before it comes out that racial differences in IQ are due to differing allele frequency as well as gene expression.