Mates of schizophrenic mothers. A study of assortative mating from the American-Danish high risk project.

Both mates of schizophrenic mothers and a control group consisting of mates of non-schizophrenic mothers were diagnostically examined. The former were more frequently psychiatrically deviant than their controls, both with respect to a life-time syndrome diagnosis and a personality diagnosis. Mating between a schizophrenic mother and a father who suffered from schizophrenia spectrum disorder significantly increased the offspring's risk of developing a schizophrenia spectrum disorder himself. Assortative mating was negatively correlated with age of onset of maternal schizophrenia. It is proposed that defective emotional rapport or sub-psychotic features constitute the phenotypic traits by which assortative mating operates in schizophrenia.