Marital Satisfaction as a Moderator of Molecular Genetic Influences on Mental Health

The quality of one’s romantic relationship is associated with mental health. Low levels of relationship quality may be a stressor that triggers a predisposition or diathesis to mental illness. Analyses were conducted to examine whether relationship quality moderated the association between polygenic risk scores (PRSs) for several mental health syndromes on phenotypic measures of those syndromes. Data were drawn from the Midlife in the United States (MIDUS) study of health and well-being. A subsample was genotyped, and PRSs were calculated. The PRS for anxiety was more strongly related to the anxiety phenotype when satisfaction was low than when satisfaction was high, providing evidence of a genetic susceptibility process between marital distress and anxiety. The expression of genetic influences on a phenotype in the presence of certain environmental stressors is complex and may depend on the specific phenotype and the methodology by which genetic influences are estimated.