A genetic study of hypertension in Okamoto-Aoki spontaneously hypertensive rats

Summary Data from crosses between Wistar/Furth rats and spontaneously hypertensive rats indicate that there are a small number of genes (3 to 4) controlling the hypertension trait in the Okamoto-Aoki spontaneously hypertensive rats. However, F 1 rats bred from reciprocal crosses of Sprague-Dawley rats and spontaneously hypertensive rats were hypertensive. F 2 rats bred from these F 1 × F 1 rats showed a 3 to 1 segregation ratio of hypertensive to normotensive rats. Furthermore, male progeny from Sprague-Dawley × F 1 backcross segregated into a 1 : 1 ratio of hypertensive to normotensive rats. These data suggest that among those 3 to 4 genes that control hypertension in the spontaneously hypertensive rats there is at least one major gene. This locus is not sex-linked but its expression is modified by sex differences.