ObjectiveBoth physiologic and pharmacological data have implicated the nitric oxide (NO) signaling cascade in the regulation of blood pressure in humans and its impairment in the pathogenesis of hypertension. In biological systems, the principal receptor for NO is NO-stimulated guanylyl cyclase. NO-stimulated guanylyl cyclases are obligate heterodimers (α/β). The genes for guanylyl cyclase subunits α1, β1, and β2are likely candidates for causing hypertension in the Dahl rat as their expression is altered and their gene loci are closely linked to known quantitative trait loci for blood pressure in Dahl rat crosses. The objective of the current study was to test whether markers near guanylyl cyclase subunit genes were linked to hypertension in Caucasians.DesignTo test for linkage of genetic markers in or near the guanylyl cyclase genes to hypertension in Caucasians, a sample of 124 Utah hypertensive sib pairs was genotyped.ResultsFour highly polymorphic markers in or near the human guanylyl cyclase subunits homologous to the rat α1(human chromosome 8), rat β1(human chromosome 4), and rat β2(human chromosme 13) genes showed no evidence of excess allele sharing in the set of hypertensive sibships.ConclusionWe conclude that the heterodimeric guanylyl cyclase subunit loci do not appear to be linked to hypertension in Caucasians.