Inheritance of risk
Sequence variants in the parental genomes that are not transmitted to the offspring are often ignored in genetic studies. Non-transmitted alleles can affect the offspring through their impacts on the parents and other relatives, a phenomenon we call “genetic nurture.” Through the study of the non-transmitted alleles, Kong et al. (1) demonstrated that genetic nurturing effects exist and can have an impact on variance explained. These results also reveal that the observed effects from GWAS do not necessarily reflect direct effects alone. They can be amplified by genetic nurturing effects and, to a lesser extent, assortative mating–induced confounding.
Owing to power considerations, we will mostly study variants as an aggregate. We will study, in a large sample, how the non-transmitted alleles for various traits, including psychiatric, personality, educational attainment and cognition affect the risk of cardiovascular and other health-related traits. For this analysis, we will make use of a unique Nordic sample consisting of trios and extended families (N = 250,000).
(1) Kong et al (2018) The nature of nurture: Effects of parental genotypes Science Vol. 359, Issue 6374, pp. 424-428 DOI: 10.1126/science.aan6877