Zeroing in on the Genetics of Intelligence

Despite the high heritability of intelligence in the normal range, molecular genetic studies have so far yielded many null findings. However, large samples and self-imposed stringent standards have prevented false positives and gradually narrowed down where effects can still be expected. Rare variants and mutations of large effect do not appear to play a main role beyond intellectual disability. Common variants can account for about half the heritability of intelligence and show promise that collaborative efforts will identify more causal genetic variants. Gene–gene interactions may explain some of the remainder, but are only starting to be tapped. Evolutionarily, stabilizing selection and selective (near)-neutrality are consistent with the facts known so far.

[1]  W. Iacono,et al.  Results of a “GWAS Plus:” General Cognitive Ability Is Substantially Heritable and Massively Polygenic , 2014, PloS one.

[2]  Ian J. Deary,et al.  Common genetic variants associated with cognitive performance identified using the proxy-phenotype method , 2014, Proceedings of the National Academy of Sciences.

[3]  D. Boomsma,et al.  Mendelian and polygenic inheritance of intelligence: A common set of causal genes? Using next-generation sequencing to examine the effects of 168 intellectual disability genes on normal-range intelligence , 2015 .

[4]  Ruben C. Arslan Evolutionary Genetics , 2014 .

[5]  Molly Przeworski,et al.  Determinants of mutation rate variation in the human germline. , 2014, Annual review of genomics and human genetics.

[6]  Ruben C. Arslan,et al.  The Effect of Paternal Age on Offspring Intelligence and Personality when Controlling for Parental Trait Levels , 2013, PloS one.

[7]  Martin S. Taylor,et al.  Exome Sequencing to Detect Rare Variants Associated With General Cognitive Ability: A Pilot Study , 2015, Twin Research and Human Genetics.

[8]  R. Plomin,et al.  Genome-wide estimates of inbreeding in unrelated individuals and their association with cognitive ability , 2013, European Journal of Human Genetics.

[9]  A Hofman,et al.  Genetic contributions to variation in general cognitive function: a meta-analysis of genome-wide association studies in the CHARGE consortium (N=53 949) , 2015, Molecular Psychiatry.

[10]  L J Whalley,et al.  Human cognitive ability is influenced by genetic variation in components of postsynaptic signalling complexes assembled by NMDA receptors and MAGUK proteins , 2014, Translational Psychiatry.

[11]  Jaap J. A. Denissen,et al.  The evolutionary genetics of personality , 2007 .

[12]  P. Scheet,et al.  Intelligence: shared genetic basis between Mendelian disorders and a polygenic trait , 2015, European Journal of Human Genetics.

[13]  Lorna M. Lopez,et al.  Genetic Copy Number Variation and General Cognitive Ability , 2012, PloS one.

[14]  Robert Plomin,et al.  LISREL modeling: Genetic and environmental influences on IQ revisited , 1990 .

[15]  R Plomin,et al.  Genetics and intelligence differences: five special findings , 2014, Molecular Psychiatry.

[16]  Jonathan P. Beauchamp,et al.  Most Reported Genetic Associations With General Intelligence Are Probably False Positives , 2012, Psychological science.

[17]  A. Sjölander,et al.  Paternal age at childbearing and offspring psychiatric and academic morbidity. , 2014, JAMA psychiatry.

[18]  D. Posthuma,et al.  Reconsidering the Heritability of Intelligence in Adulthood: Taking Assortative Mating and Cultural Transmission into Account , 2011, Behavior Genetics.

[19]  A. McRae,et al.  No Association Between General Cognitive Ability and Rare Copy Number Variation , 2013, Behavior Genetics.

[20]  R. Marioni,et al.  The total burden of rare, non-synonymous exome genetic variants is not associated with childhood or late-life cognitive ability , 2014, Proceedings of the Royal Society B: Biological Sciences.

[21]  L. Vissers,et al.  Genome sequencing identifies major causes of severe intellectual disability , 2014, Nature.