Association of interleukin-1β genetic polymorphisms with obstructive sleep apnea syndrome

Abstract

To investigate the association between interleukin (IL)-1β genetic polymorphisms and obstructive sleep apnea syndrome (OSAS). Totally 850 individuals with hypertension were included. All of them were checked by polysomnography in the Hypertension Center of People's Hospital of Xinjiang Uygur Autonomous Region from January to December in 2010. According to the results of polysomnography, these subjects were divided into non-OSAS group (n=225)and OSAS group (n=625). Genetic variations were sequenced and screened at loci over functional region of IL-1β gene in 96 patients with severe OSAS.The typical loci were selected for genotyping by TaqMan-polymerase chain reaction in 850 subjects. One novel and 5 known variations in the IL-1β gene were identified, and then three representative mutation loci were selected for genotyping.The allele frequency distribution of rs1143633 was significantly different between the OSAS and non-OSAS groups in the total and male populations (χ(2)=9.258, P=0.002;χ(2)=5.119, P=0.024, respectively). Although the parameters of sleep apnea monitoring showed no significant difference in individuals with CC, CT, and TT genotypes of rs1143633 in total, male, and female populations (P>0.05), the median of the apnea hypopnea index of CT genotype was significantly higher than that of CC and TT in total and male populations and the mean of the lowest blood oxygen saturation increased in individuals with CC, CT, and TT genotypes of rs1143633 in total and male populations.Haplotype was no significantly associated with OSAS in total,male,and female populations(P>0.05).Logistic regression analysis showed that CT genotype of rs1143633 variation was a risk factor for OSAS in total and male populations (OR=1.574,95% CI=1.061-2.437,P=0.042;OR=1.887,95% CI=1.091- 3.265,P=0.023). The rs1143633 polymorphism in IL-1β gene may be associated with OSAS.