Clinicogenetic studies within the scope of Leonhard taxonomy

Using conventional genealogical methods and genetic correlation analysis, the author investigates Leonhard's classification of schizophrenias and cycloid psychoses. According to the second of these methods, the systematic schizophrenias and cycloid psychoses definitely diverge on account of the phenotypic correlations, whereas the unsystematic group presumably occupies a median genetic position between the two categories first mentioned.