Genetic influences on parenting are partially explained by parental internalizing symptoms

Parents who experience higher levels of depression and anxiety symptoms tend to engage in more negative parenting (high conflict and harshness). Both internalizing symptoms and parenting are genetically influenced, and prior... [ view full abstract ]

Parents who experience higher levels of depression and anxiety symptoms tend to engage in more negative parenting (high conflict and harshness). Both internalizing symptoms and parenting are genetically influenced, and prior studies have shown that parent characteristics such as anxious personality traits share genetic underpinnings with negative parenting. The present study uses a sample of twin parents of adolescents (Twin and Offspring Study in Sweden: TOSS) to assess the contributions of genetic, shared environmental, and non-shared environmental influences on the overlap between parental internalizing symptoms and parenting behavior. TOSS is comprised of 909 pairs of same-sex twin parents of an adolescent n = 386 MZ pairs, 63% female, Mage = 44.89 years, SD = 4.89). Adolescent cousin pairs were same-sex and within 4 years of age of one another (Mage = 15.75 years, SD = 2.40  49% female). Twins reported on their own internalizing symptoms using the Center for Epidemiological Studies Depression scale and the psychic and somatic anxiety subscales of the Karolinska Scales of Personality. Twin parents also reported on their harsh or conflictual parenting using the Child Rearing Issues and Expressed Emotion measures. Composite scores were created for parent-rated internalizing and negative parenting and were significantly correlated (r = 0.31, p < 0.001). A correlated bivariate factor model indicated that parental internalizing symptoms and negative parenting were explained by genetic and nonshared environmental influences (A = 51% E = 49%; A = 34% E = 64%, respectively) with a significant genetic (r_g = .44, p < .01) and nonshared environmental (r_e = .24, p < .01) correlation between the two constructs. Shared environmental influences did not contribute to either parental internalizing symptoms or to negative parenting, thus there was with no significant contribution of shared environmental influences to the covariance of the two. Additional analyses found no evidence of differences between mothers and fathers.