Before posting up Piffer’s paper, I sent it to a reviewer, someone who works in intelligence research. I explained that many geneticists were dismissive about Piffer’s work on group intelligence, and asked for a critical opinion. Here is that opinion, and Piffer’s replies. Piffer also includes responses to the main themes which came out of... Read More

The figure shows standardized polygenic scores by population for Education GWAS, in descending order (1000 Genomes Populations, EA MTAG, N= 3,257 SNPs). One function of a blog is to let people shoot down ideas. Conjectures have a short half-life. Refutations always snap at their heels. David Becker, whose latest version of country IQs received trenchant... Read More

The “missing heritability” problem: current genetic analysis cannot explain as much variance as that suggested by population heritability estimates. This has been a cue for “Down with twin studies” arguments, in which those of dramatic inclinations have chosen to imagine that heritability estimates were thereby disproved. Not so. I was never particularly worried about this... Read More

The intelligence gene hunters have been stepping up their activities, and keep coming back with more trophies. Danielle Posthuma and colleagues are at it again, studying very large samples and finding further novel genes which load on brain tissues. I hope someone somewhere is keeping track of the overall picture, perhaps in a control room... Read More

In my last post I said: I had no idea that my thesis would receive instant support the following day in a paper which begins with a stirring paragraph, worth quoting in full: Since its discovery in 1904, hundreds of studies have replicated the finding that around 40% of the variance in people’s test scores... Read More

Jim Flynn once observed that no-one was funding research into the genetics of racial differences in intelligence because they feared they would find something. Here is my psychologist’s summary of where we are as regards the genetics of intelligence in general: 10%. That is to say, by poking about in the genetic code researchers can... Read More