An analysis of the genetics of schizophrenia

Abstract

Data on the inheritance of schizophrenia indicate that both genetics and environment contribute importantly to the manifestation of the disease. However, heterogeneity of the data makes an accurate analysis very difficult. In this paper, a crude analysis of a threshold model, using a polygenic or a single gene hypothesis, shows that both are in approximate agreement with the data. Though argument about genetic models seems futile when virtually any model can account for the data, the single gene hypothesis is unavoidably more attractive at this stage. If a single gene is involved, the allele predisposing toward schizophrenia should be considered as essentially, though not entirely, recessive; all genotypes would be strongly affected by unknown environmental factors; and even some genetically normal individuals would manifest the disorder.