For example, hypertension in EPHB6 KO is only observed in castrated mice26; hypertension after Efnb3 KO is present in females but not males; the BP phenotype in Efnb3 KO mice is reversed after gonadectomy: castrated KO males become hypertensive, while ovariectomized KO females, normotensive29; on the other hand, male but not female Efnb2 and Ephb4 KO mice are hypotensive27, 30. This evidence concerns the gene EFNB3 and Hypertension.