A STUDY OF ENZYMES INVOLVED IN CATECHOLAMINE METABOLISM IN PARENTS OFPATIENTS WITH SCHIZOPHRENIA

The concentrations of serum homovanillic acid (HVA), norepinephrine (N E), tyrosine (Tyr), phenylalanine (Phe) and tryptophan (Trp), and the activities of serum dopamine-beta-hydroxylase (DBH), platelet monoamin e oxidase (MAO), and erythrocyte catechol-O-methyl transferase (COMT) were measured in 68 healthy parents who had schizophrenic offspring. T he results show a significant correlation between the parents of schiz ophrenic patients in serum HVA (r=0.38, n=34, p<0.05), NE (v=0.40, n=3 3, p<0.02), Phe (r=0.44, n=34, p<0.01), Tyr (r=0.43, n=34, p<0.02) and DBH activity (r=0.51, n=30, p<0.005), but do not show a significant c orrelation in erythrocyte COMT (r=0.01, n=27), platelet MAO (r=0.04, n =23) or serum Trp (r=0.10, n=34). There were no significant correlatio ns in these measurements between randomly matched parents. The present study suggests that both parental sides of schizophrenic patients are likely to have similar alleles associated with the catecholamine path way, and their ill offspring may possess a double dose of the schizoph renogenic alleles.