Jacobus (Koos) Boomsma

University of Copenhagen

 

Genes with parent-of-origin imprints or copy number variation have been proposed to increase/decrease placental provisioning and maternal investment after lactation, driven by the non-zero likelihood that her next child may be a half- rather than full-sibling of the focal offspring. We used the national health registries of Denmark to test whether phenotypic markers of parent-specific gene dosage effects at conception affect physical and mental health later in life. The first study analyzed exposure to pregnancy-related hypertension in the womb and found that the healthiest cohort had mothers with mildly elevated blood pressure in the first trimester but not later in pregnancy. The second study tested Crespi and Badcock’s hypothesis that autism and schizophrenia are opposite ends of a continuum around normal cognition, with the respective risks of these mental diseases uni-directionally increasing/decreasing with size at birth. The results of both studies were consistent with the evolutionary predictions that inspired the work and may help explain why pre-eclampsia, autism and schizophrenia have not been removed by selection in our ancestral human populations.