Marital resemblance for obsessive–compulsive, anxious and depressive symptoms in a population-based sample

Abstract

Background. Resemblance between spouses can be due to phenotypic assortment, social homogamy and/or marital interaction. A significant degree of assortment can have consequences for the genetic architecture of a population. We examined the existence and cause(s) of assortment for obsessive-compulsive (OC), anxious and depressive symptoms in a population-based twin-family sample.Method. OC, anxious and depressive symptoms were measured in around 1400 twin-spouse pairs and >850 parent pairs. Correlations of twins and their spouse, twin and co-twin's spouse, spouses of both twins and parents of twins were obtained to consider phenotypic assortment versus social homogamy as possible causes of marital resemblance. The association of length of relationship with marital resemblance was also investigated. Finally, we examined whether within-trait or cross-trait processes play a primarily role in marital resemblance.Results. Small but significant within-trait correlations of between 0.1 and 0.2 were seen for spouse similarity in OC, anxious and depressive symptoms. Cross-correlations were significant but lower. There was no correlation between length of relationship and marital resemblance. From the pattern of correlations for twin-spouse, co-twin-spouse and spouses of both twins, phenotypic assortment could not be distinguished from social homogamy. Both within-and cross-assortment processes play a role in marital resemblance.Conclusions. Small within-and across-trait correlations exist for OC, anxious and depressive symptoms. No evidence for marital interaction was found. Spouse correlations are small, which makes it difficult to distinguish between social homogamy and phenotypic assortment. It is unlikely that correlations of this size will have a large impact on genetic studies.

Population-Based, Multigenerational Family Clustering Study of Obsessive-compulsive Disorder

“…33 Finally, the possibility of geneenvironment correlations should also be investigated because it is plausible that genetic factors could influence the specific environmental experiences of children who are vulnerable to developing OCD. 34 Nonbiological Relatives of Patients With OCD Are Also at Elevated Risk for OCD To our knowledge, an increased risk for clinically diagnosed OCD in spouses or partners sharing children with OCD probands has not been previously reported but is consistent with the results of a previous study 35 in a community-based sample of Dutch twins and their spouses. The present study design did not enable delineating possible marital interaction effects from assortative mating, or social homogamy.…”

Heritability, Assortative Mating and Gender Differences in Violent Crime: Results from a Total Population Sample Using Twin, Adoption, and Sibling Models

“…The effect this would have on the genetic correlation of mating partners would depend on the proportion of shared genetic and environmental elements that cause the correlation between the phenotypes, and could be larger than under primary phenotypic assortment. This is not testable in the present data, but the observed r Sib1-P1 is already remarkably high compared to most other studied phenotypes (Maes et al 1998;van Grootheest et al 2008), and another study of assortative mating of antisocial behaviour found that antisocial acts were more strongly assorted for than were associated personality traits or attitudes (r behaviour = 0.53, r personality = 0.15) (Krueger et al 1998). Even if these processes were present, we believe it to be unlikely that the true genetic correlation is outside the range of values presented in Table 5.…”

Genetic and Environmental Contributions to Self-Report Obsessive-Compulsive Symptoms in Dutch Adolescents at Ages 12, 14, and 16

“…36 Second, the use of twin models requires several assumptions, including the absence of assortative mating, the equal environment assumption, and the absence of geneYenvironment interaction and correlation. van Grootheest et al 37 found that small, but significant assortative mating existed for OC symptoms but concluded that the bias in twin studies caused by the small amount of assortment is negligible. Jonnal et al 18 tested the equal environment assumption for OC symptoms and concluded that the equal environment assumption was not violated.…”