Relationship between schizophrenia polygenic risk scores and schizotypy: dimensional and taxonomic approaches

Abstract

Schizotypy is considered as a phenotype that reflects preclinical manifestations of a genetic predisposition to schizophrenia. There are two views on the nature of this relationship - dimensional and taxonomic. Previous studies on the contribution of schizophrenia polygenic risk scores (PRS) to schizotypy were conducted in Western European populations using the dimensional model and yielded negative results. The objective of this study was to assess the relationship between schizophrenia PRS and dimensions and taxa of schizotypy in the Russian population. Methods. Genome-wide data were obtained from a sample of 290 healthy subjects belonging to the clusters of individuals with low, positive, negative, and high mixed schizotypy. Schizotypy was measured using the Schizotypal Personality Questionnaire (SPQ). Results. The schizophrenia PRS did not correlate with cognitive-perceptual, paranoid, interpersonal, or disorganized SPQ factors. Taxon-like groups (clusters) differed in PRS at a trend level, with the highest PRS being found in the high mixed schizotypy group. Conclusion. The results are consistent with the assumption of the taxonomic model of schizotypy that in some healthy individuals with a high degree of schizotypal personality traits, these traits reflect the genetic predisposition to schizophrenia.