Recent research has indicated that individuals diagnosed with a major psychiatric disorder are more likely than healthy individuals to select a mate with their own or an alternative psychiatric condition. What role this nonrandom mating may play in the transmission of psychiatric illness, however, remains unclear. Where parents are homotypic for a disorder (e.g., both parents have a diagnosis of schizophrenia), offspring will receive genetic variants from each parent that are related to that disorder ? placing them at particularly high genetic risk for that condition's development. However, this type of compounded genetic risk may also occur in heterotypic pairings (e.g., one parent having schizophrenia, the other bipolar disorder), as many psychiatric conditions share genetic risks. With prior research suggesting that such heterotypic pairings are pervasive in psychiatric populations, understanding the degree to which risks are sustained in these offspring is an important question. The primary goal of this proposal is, therefore, to leverage the unique scale of data available in the Swedish Medical Registers to determine the change in risk for major psychiatric diagnoses, among the offspring of parents who are homotypic or heterotypic for major psychiatric diagnoses, relative to the risk in offspring of single affected or healthy parents. Parents with any of eight major psychiatric diagnoses - attention deficit hyperactivity disorder, bipolar disorder, generalized anxiety disorder, major depressive disorder, obsessive- compulsive disorder, schizophrenia, social phobia, and substance abuse ? will be considered in this work, with the incidence of these conditions in their offspring compared to the incidence in matched population controls. In addition to describing these risks, this project also proposes to examine the degree of overlap in risk variants for a particular condition ? schizophrenia ? among the parents of offspring diagnosed with this condition. If found, this type of molecular correlation would signal a clear mechanism by which a disorder may arise in offspring of homo- or heterotypic pairs, while its absence could suggest a stronger role for environment in shaping these added risks.
Studies have indicated that individuals with psychiatric disorders mate non-randomly: a process that may increase the risk for psychiatric conditions in the offspring of these pairings, as both partners will carry (be correlated for) genes linked to these conditions. In this study, we use large-scale medical data to investigate whether having two parents with the same or differing psychiatric illnesses has an impact on the psychiatric outcomes of their children, and to what extent these impacts differ relative to offspring of parents in which only one parent is affected or both parents are healthy. In addition, using genetic testing techniques, we will examine whether the genes of mated partners are more highly correlated than the genes of random individuals.
| Mataix-Cols, D; Frans, E; Pérez-Vigil, A et al. (2018) A total-population multigenerational family clustering study of autoimmune diseases in obsessive-compulsive disorder and Tourette's/chronic tic disorders. Mol Psychiatry 23:1652-1658 |
