Cosegregation of blood pressure with a kallikrein gene family polymorphism.

It has recently been proposed that sequence variation in the gene coding for tissue kallikrein might be involved in the pathogenesis of hypertension. However, molecular evidence of an association between a sequence alteration in the kallikrein gene family and the transmission of increased blood pressure has never been reported. In 32 recombinant inbred (RI) strains derived from the spontaneously hypertensive rat (SHR) and the normotensive Brown Norway rat (BN), we investigated whether a restriction fragment length polymorphism (RFLP) marking the kallikrein gene family cosegregated with blood pressure. In the RI strains that inherited the kallikrein RFLP from the SHR progenitor strain, the median systolic, diastolic, and mean arterial pressures were significantly greater than in the RI strains that inherited the kallikrein RFLP from the BN progenitor strain. These findings suggest that in the rat, sequence variation in the kallikrein gene family, or in closely linked genes, may have the capacity to affect blood pressure.