[Association between genetic polymorphisms of HIF-2α gene and high altitude pulmonary hypertension in Han population].

Objective: To test the hypothesis that the single nucleotide polymorphisms (SNPs) in HIF-2α gene were associated with the susceptibility of high altitude pulmonary hypertension (HAPH) in Han population in China. Methods: Those Han population who emigrated to plateau (average altitude 3 300 m) and have been lived here for more than 20 years were included as the research subjects, the method of cluster random sampling was used to enroll 49 HAPH patients as the case group (HAPH group) and 39 free of HAPH people as the control group. The Sanger chain termination method was used to detect the SNPs of rs1562453, rs1867785, rs4953361, rs7598371 and rs11125068 in HIF-2α gene. Results: The genotype and frequencies of rs1562453 were CC (49.0%), CT (46.9%) and TT (4.1%) in the HAPH group, and the locus's genotype and frequencies were CC (76.9%), CT (17.9%) and TT (5.1%) in the control group. The alleles and frequencies of rs1562453 were C (72.4%) and T (27.6%) in the HAPH group, and the locus's alleles and frequencies were C (85.9%) and T (14.1%) in the control group. Their genotypes and alleles frequencies were of significant difference between the two groups (genotypes P=0.017; allele P=0.031). Meanwhile, The genotype and frequencies of rs1867785 were AA (46.9%), AG (46.9%) and GG (6.1%) in the HAPH group, and the locus's genotype and frequencies were AA (74.4%), AG (25.6%) and GG (0.0%) in the control group. The alleles and frequencies of rs1867785 were A (70.4%) and G (29.6%) in the HAPH group, and the locus's alleles and frequencies were A (87.2%) and G (12.8%) in the control group. Their genotypes and alleles frequencies were of significant difference between the two groups (genotypes P=0.020; allele P=0.008). Genotypes frequencies of the rs1562453 and rs1867785 were analyzed by Logistic Regression which showed that the genotypes frequencies of rs1562453 were also of significant difference between two groups (Wald=9.561, P=0.008), CT vs CC (β=1.720, OR=5.580, P=0.011). Conclusion: The SNPs of rs1562453 in HIF-2α gene may be associated with the development of HAPH among Chinese Han population, and individuals with the genotype CT may be more vulnerable to HAPH than those who carry genotype CC, and allele T may be a risk factor for HAPH.