The British Journal of Psychiatry 140: 595-599 (1982)
© 1982 The Royal College of Psychiatrists
MT Tsuang, KD Bucher and JA Fleming
Segregation analysis was applied to blind family data concerning schizophrenia to decide if the transmission of schizophrenia could be explained by a single major gene. Our results showed that the Mendelian model was unacceptable. Therefore, the monogenic hypothesis could not account for the transmission of schizophrenia. Since the hypothesis of no parent-child transmission was also not accepted, there was an indication that some form of vertical transmission existed which could be psychosocial, or an interaction between genetic and psychosocial factors. Our results suggest genetic heterogeneity in schizophrenia. Currently available clinical criteria for defining subgroups must be improved in conjunction with detection of biological indicators so that segregation analysis of family data could be effectively used in determining modes of transmission in schizophrenia.