Association Between Genetic Polymorphisms Of BDKRB₂ And Essential Hypertension

Objective To study the association between -58T/C polymorphism in the promoter and 181T/C polymorphism in the exon 2 of BDKRB2 gene and essential hypertension disease (EH) in Chong qing.Methods The genotypes of BDKRB2 were detected by sequence specific primer polymerase chain reaction(SSP-PCR) in 95 EH patients and 157 healthy controls. The level of BDKRB2 mRNA was determined by real time-polymerase chain reaction (RT-PCR).Results 1. There were significant differences in frequencies of allele and genotype in -58T/C polymorphisms between EH and control groups respectively (P<0.05) .The relative risk of EH with CC genotype was 3.5 times of those with TT genotype (P=0.004, OR=3.5, 95%CI: 1.509-8.116). 2. There were significant differences in frequencies of allele and genotype in 181T/C polymorphisms between EH and control groups respectively (P<0.05) .The relative risk of EH with CT+TT genotype was 3.4 times of those with CC genotype (P=0.012, OR=3.397, 95%CI: 1.304-8.850). 3. There were significant differences both in SBP and DBP of different genotypes of -58T/C (pSBP = 0.048, pDBP = 0.008). Moreover, the SBP of CC genotype was higher than that of CT and TT genotype by 4 mmHg and 13 mmHg respectively. The DBP of CC genotype was higher than that of CT and TT genotype by 3 mmHg and 9 mmHg respectively. There was no statistical difference between groups in 181T/C genotypes. 4. There was no significant difference after the combination of various genotypes of the two locus analyzing the relationship between EH and combination genotypes by Logistic regression analysis. 5. Construction of -58T/C and 181T/C haplotype: D'value was 0.12 and r2 value was 0.001, which was not available for constructing haplotype.6.The level of BDKRB2 mRNA had a significant difference between EH group and control group (P=0.000).Conclusion1. Polymorphism of BDKRB2 -58T/C might be associated with EH, and C allele might be a marker for susceptibility of EH;2. Polymorphism of BDKRB2 181T/C might be associated with EH, and T allele might be a marker for susceptibility of EH;3. -58T/C and 181T/C regulated blood pressure independently;4. The level of BDKRB2 mRNA in EH was lower than that in control group.