Heritability of forskolin and hormone-stimulated adenylate cyclase activity in human lymphocytes

Isoproternol, prostaglandin E₁ and forskolin-stimulated cyclic AMP accumulation were compared in intact lymphocytes obtained from nine monozygotic and nine sib pairs matched for age and sex. Heritability was calculated by three different methods, two based on the intraclass correlation coefficients and one based directly on the variance. Only for forskolin is a significant proportion of variance (0.68-0.91) attributable to genetic factors, suggesting that forskolin-stimulated activity may prove to be a valuable genetic marker in studies of human pathology. Neither basal nor isoproternol and prostaglandin E₁-stimulated activity show significant heritability in intact human lymphocytes. The individual differences observed in levels of beta-adrenergic and prostaglandin stimulated receptor activity in human lymphocytes are, therefore, most likely due to environmental factors.