[A case-control study of pregnancy-induced hypertension with a genetic predisposition: association of a molecular variant of angiotensinogen in the Japanese women].
Pregnancy-induced hypertension (PIH) is considered to be a multifactorial disease. Genetic background plays an important role for the pathogenesis of PIH as well as environmental effects. Recently, an association between PIH and a molecular variant of angiotensinogen (AGT) gene, which encodes methionine (M235) or threonine (T235) at residue 235, was reported both in Caucasians and the Japanese women. In Caucasians, T235 was associated with preeclamptic primiparas (PE-PP), a diagnostic subgroup of PIH. However, in the Japanese, an association of T235 with PE-PP is not yet proven probably because of small sample size. To investigate this point, the author performed a case-control study, collecting 139 PIH samples including 68 PE-PP and 278 cases of age and parity (primiparous or multiparous) matched controls in Hokkaido area. Molecular variants of their AGT genes were typed by the method using polymerase chain reaction (PCR). Results showed frequencies of homozygote of T235 were significantly higher in PIH (80%, p < 0.001), PE-PP (87%, p < 0.001) and severe PE-PP (92%, p < 0.001) than in controls (56%). In the Japanese, the frequencies were significantly higher in PE-PP than in other forms of PIH (73%, p < 0.05), which is the same tendency as previously reported in Caucasians. The present results indicate that AGT is involved in the pathogenesis of both PIH and PE-PP in the Japanese women.