Abstract-Essential hypertension has a genetic basis. Accumulating evidence, including findings of elevation of arterial blood pressure in mice lacking the endothelial nitric oxide synthase (eNOS) gene, strongly suggests that alteration in NO metabolism is implicated in hypertension. There are, however, no reports indicating that polymorphism in the eNOS gene is associated with essential hypertension. We have identified a missense variant, Glu298Asp, in exon 7 of the eNOS gene and demonstrated that it is associated with both coronary spastic angina and myocardial infarction. To explore the genetic involvement of the eNOS gene in essential hypertension, we examined the possible association between essential hypertension and several polymorphisms including the Glu298Asp variant, variable number tandem repeats in intron 4 (eNOS4b/4a), and two polymorphisms in introns 18 and 23. We performed a large-scale study of genetic association using two independent populations from Kyoto (nϭ458; 240 normotensive versus 218 hypertensive subjects) and Kumamoto (nϭ421; 223 normotensive versus 187 hypertensive subjects), Japan. In both groups, a new coding variant, Glu298Asp, showed a strong association with essential hypertension (Kyoto: odds ratio, 2.3 [95% confidence interval, 1.4 to 3.9]; Kumamoto: odds ratio, 2.4 [95% confidence interval, 1.4 to 4.0]). The allele frequencies of 298Asp in hypertensive subjects were significantly higher than those in normotensive subjects in both groups (Kyoto: 0.103 versus 0.050, PϽ0.0017; Kumamoto: 0.120 versus 0.058, PϽ0.0013, respectively). No such disequilibrium between genotypes was significantly associated with any other polymorphisms we examined; the Glu298Asp variant was also not linked to any other polymorphisms. In conclusion, the Glu298Asp missense variant was significantly associated with essential hypertension, which suggests that it is a genetic susceptibility factor for essential hypertension.(Hypertension. 1998;32:3-8.)Key Words: genes Ⅲ nitric oxide synthase Ⅲ hypertension, essential Ⅲ polymorphism Ⅲ genetics W ith a genetic contribution of from 25% to 60%, human essential hypertension has a genetic basis. Among persons younger than age 50 years, essential hypertension occurs 3.8 times more often in those having two or more first-degree relatives who developed high blood pressure before age 55.1 NO synthesis by the vascular endothelium is important for the regulation of vasodilator tone and the control of blood pressure in humans.2 A recent study using mice with disrupted eNOS gene revealed that eNOS function is required for vascular and hemodynamic responses to acetylcholine and that the disruption of the eNOS gene leads to hypertension. 3 Moreover, recent reports demonstrate that whole-body NO production in patients with essential hypertension is diminished under basal conditions, as established by measurement of urinary and plasma nitrate. 4 In addition, the offspring of hypertensive patients exhibit a reduced response to acetylcholine linked to a defect in the NO pathway.5...

The human leukocyte antigen is a crucial genetic factor that initiates or regulates immune response by presenting foreign or self antigens to T lymphocytes. The aim of this study was to investigate whether HLA polymorphism is associated with the onset or progression of liver injury in

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To assess the association between HLA-DRB1 and the pathogenesis of rheumatoid arthritis (RA) in the Japanese population, we typed for HLA-DRB1 alleles in 852 Japanese patients. An analysis of HLA-DRB1 allele associations was performed on the overall group and in three disease subsets of adult-onset RA, classified according to the extent of joint destruction evident on plain radiograms, i.e. least erosive subset (LES), more erosive subset (MES) and most erosive subset with mutilating disease (MUD). The Japanese RA patients with positively associated with DRB1*0101 and *0405, and negatively associated with DRB1*0701, *0802, *1302 and *1405. DRB1*0101 was associated more strongly with a milder disease subset and the relative risk (RR) was 1.9, 1.5 and 1.2 for LES, MES and MUD, respectively. On the other hand, DRB1*0405 was associated more strongly with a more severe disease subset, the RR being 1.8, 4.0 and 4.3 for LES, MES and MUD, respectively. These findings suggest that RA is a heterogeneous disease, not only clinically, but also in terms of its immunogenetic background, and that HLA-DRB1 can be a useful prognostic factor for RA.

Hematopoietic function of some aplastic anemia (AA) patients is dependent on the administration of cyclosporine (CyA). To investigate whether certain HLA class II genes are associated with susceptibility to such CyA-dependent AA, we determined the HLA class II alleles of 59 AA patients treated with CyA. Among 26 patients successfully treated with CyA, 13 required a small dose of CyA to maintain stable hematopoiesis. Of these 13 AA patients, 10 shared an HLA class II haplotype of DRB1*1501-DQA1*0102-DQB1*0602. None of the 13 responders who obtained a sustained remission off CyA therapy possessed this haplotype. In the 10 patients who shared the HLA class II haplotype, single-strand conformation polymorphism analysis of each gene fragment of this haplotype failed to detect a polymorphism in the nucleotide sequence. When the AA patients were assessed for their likelihood to respond to CyA therapy, the response rate in patients with this haplotype (71%) was significantly higher than that of patients with another haplotype associated with HLA-DR2, DRB1*1502-DQA1*0103- DQB1*0601 (36%) and that of patients without HLA-DR2 (35%). These findings indicate that the CyA-dependent response of AA is closely related to an HLA class II haplotype of DRB1*1501-DQA1*0102-DQB1*0602 and suggest that, in AA patients with this haplotype, immune mechanisms play an important role in the pathogenesis of bone marrow failure.