Sequencing the exons of human glucocorticoid receptor (NR3C1) gene in Han Chinese with high-altitude pulmonary edema

BACKGROUND: High-altitude pulmonary edema (HAPE) is a serious acute mountain sickness that mainly occurs in non-acclimatized individuals after rapid ascent to high altitude. The precise etiology of HAPE remains unclear. This study aimed to investigate whether NR3C1 gene polymorphism is associated with the susceptibility to HAPE. METHODS: The exons of NR3C1 gene were sequenced by a ABI 3730 DNA analyzer in 133 HAPE patients and matched 135 healthy Han Chinese controls from the Yushu area in Qinghai (the altitude greater than 3500 m). RESULTS: DNA sequencing showed the heterozygous substitutions at codon 588 (rs6194) in exon 6 and 766 (rs6196) in exon 9 of NR3C1 gene. The genotypic distributions and allelic frequencies of NR3C1 SNP rs6194 showed significant differences in two groups (P < 0.05). The frequencies of the C allele were significantly higher in the HAPE group than in the control group (P < 0.05) with an odds ratio of 3.009 (95% CI = 1.250-7.244). There were no differences in genotypic and allelic frequencies in rs6196 polymorphism between the two groups. CONCLUSIONS: NR3C1 gene rs6194 polymorphism is correlated with HAPE susceptibility. CC genotype and C allele of rs6194 polymorphism might increase the risk of HAPE in Han Chinese.