Study Of The Association HLA-DRB1 Gene Polymorphisms With Essential Hypertension And Left Ventricular Hypertrophy

Objective: The purpose of this study was to explore the association of the polymorphism of HLA-DRB1 alleles with EH and LVH in Yunnan Han nationality.methods: 1. The alleles of HLA-DR of 91 cases and 91 normal controls in Yunnan Han nationality were determined by polymerase chain reaction sequence specific primers (PCR-SSP).The allelic frequency was calculated, and the significance of the difference between the two groups was identified by use of the x~2 test.2. Cardiac remodeling of the hypertensive patients was measured by echocardiography, and left ventricular mass index (LVMI) was calculated; The patients were divided into two groups: EH-LVH+ group(n=43) and EH-LVH-group(n=48) according to the national standard of LVH [LVMI≥125 g/m~2(male) or≥120 g/m~2 (female)]. The common conditions between the two groups were analyzed. The difference of the frequency of the HLA-DRB1 alleles was analyzed among the control, EH-LVH+, EH-LVH- group. At the same times, the difference was analyzed between the EH-LVD-and EH-LVD+ group. Finally, the genetic risk of EH-LVH was analyzed by logistic regression.Results: 1. The frequency of HLA- DR15 allele for the case group was significantly higher than that of the control group(P=0.000, RR=4.38); while, the frequency of HLA-DR9 allele of the case group was significantly lower than that of the control group (P=0.000, RR=0.29).2. There was no difference in the clinic features—sex, age, family history of EH, diastolic pressure et al(P>0.05);but there was significant difference in the course of EH and systolic pressure between EH-LVH+ and EH-LVH-group(P<0.05).3. The frequency of HLA- DR15 of EH-LVH+ group was significantly higher than that of the control and EH-LVH-group(P<0.05).But the frequency of HLA-DR9 of EH-LVH+ was significantly lower than that of the control and EH-LVH-group(P<0.05).On the other hand, there was no difference in the frequency of HLA-DRB1 between the EH-LVD+ and EH-LVD+- group(P>0.05).4. The HLA-DR15 allele, course of hypertensive disease and systolic pressure were related with LVH when analyzed by Logistic regression. The OR value was 6.067 (95%CI:1.002～36.017); 1.263 (95%CI:1.022～1.560); 1.220 (CI95%CI:1.121～1.328) respectively.Conclusions: HLA-DRB1 alleles are related with EH and EH-LVH but not with EH-LVD in Yunnan Han nationality:1. It is possible that the HLA- DR15 is a susceptible gene of EH-LVH; HLA- DR9 is a protective gene of EH-LVH.2. Logistic regression shows: the course of EH, systolic pressure and HLA-DR15 all are possible risk factors of EH-LVH. Especially, HLA-DR15 allele is the most important one.3. It is also possible that the HLA-DR15 is a susceptible gene of EH; HLA-DR9 is a protective gene of EH. It is need to study further whether HLA-DRB1 is the same susceptible gene to EH and EH-LVH.