The Preliminary Study Of Essential Hypertension Susceptibility Genes In The Dai People In Yunnan Province

Essential hypertension is a complex disease caused by both genetic and environmental factors and is a main risk factor of cardiovascular disease. In recent 35 years, the prevalence rate among Dai people has increased dramatically. To explore the interaction of susceptibility genes and alleles in essential hypertension of Dai people will contribute to reveal the pathogenesis of essential hypertension, and further clarify the interaction and relationships of environmental selection factors, genetic factors and diseases.Because of genetic heterogeneity of essential hypertension, genes associated with hypertension may cause different results in various groups. The relationship between candidate genes reported in other populations and the dai groups is not clear. To study these candidate genes is beneficial for us to find pathogenetic genes associated with hypertension in Dai people. Na+ plays an important role in the pathogenesis of hypertension. According to the dietary habit of Dai people, study on the Na+-sensitive genes may be an important point to find out the molecular mechanism of high levels of hypertension prevalence rates in recent 35 years.Essential hypertension is a kind of complex disease, whose genetic mechanism depends on the common effects of many minor genes, and epistasis between genes would have influence on the hypertension. So far, rarely studies were focus on this. Analysis of epistasis of two candidates genes can provide more evidence for susceptibility gene of hypertension. According to the process of hypertension adjustment, we choose genes in the the renin-angiotensin-aldosterone system and genes associated with the metabolic pathway to find out the associations and epistasis effect of genes.First, we study the methodology of DNA pool pyrosequencing preliminary screening of candidate sites, then screen the hypertension candidate sites based DNA pool pyrosequencing.412 Dai patients with hypertension (case group) and 425 healthy Dai people (control people) were included in this study. Firstly, DNA pooling-PSQ was used preliminary for candidate genes, and then SNaPshot, Taqman, PCR and sequencing were used to genotype seven locus in ACE, ADD1 and CYP11B2, including ADD1_rs4963, ADD1_rs4961, ADD1_rs12503220, ACE_rs4291, ACE_rs4343, ACEI/D, CYP11B2_rs1799998 by. Finally, the association between epistasis effect of ACE and ADD1 and hypertension was studied.The optimization was established based on known associated loci pool pyrophosphate DNA sequencing method and high-throughput genotyping. The result indicates that the DNA pooling-PSQ can evaluate allele frequencies accurately, the difference of association analysis and predicted genotyping is between 0.5% and 3.2%. The result showed that the allele frequency of DNA pooling-PSQ method is relatively accurate, and the correlation analysis results are consistent with pre-genotyping. Among Dai people, there was no positive association between7 candidate loci and hypertension. However, the result of analysis of epistasis indicates that although there is no obvious correlation between single locus and hypertension, after functional analysis of epistatic effect, the correlation with hypertension significantly enhanced. In detail, when (D) deletion allele in ACE gene and G allele in ADD1 gene appears at the same time, the risk of hypertension enhanced rapidly (p=0.0014, OR=1.567,95%CI:1.189-2.067).And (D) deletion allele in ACE gene and T allele in CYP11B2 gene appears at the same time, the risk of hypertension increased rapidly (p=1.58E-08, OR=2.320,95%CI:1.728-3.116). no statistically positive results were found under other assumptions.Our results showed that association genes of hypertension are various in different ethnic groups, and the mechanism may be different in different populations. Due to the nature of minor genes, analysis of epistasis is a better strategy. Studies on susceptible genes with essential hypertension (EH) among Dai people and interaction among environmental factors such as diet and genetic factors will provide more clues for its pathogenesis research.