Association of tumor necrosis factor-α gene polymorphism (-308) and obstructive sleep apnea-hypopnea syndrome

Background and aim: Elevated serum tumor necrosis factor-α (TNF-α) concentra-tion and a polymorphism of the TNF-α gene at the position -308 in the promoter region are associated with obstructive sleep apnea-hypopnea syndrome (OSAHS). We aimed to determine the association of this polymorphism with OSAHS in Greek patients.

Patients and methods: A blood sample was obtained from 220 patients clinicaly diagnosed with OSAHS and 319 normal controls. TNF-α genotype was determined from nucleus-containing cells from whole blood using a PCR method.

Results: The results demonstrated that the distribution of alleles was significantly dif-ferent when comparing the OSAHS patients group to the healthy controls. The appearance of AA (p=0.04) and AG (p<0.001) genotypes was significantly greater in OSAHS patients (8.6% and 32.7%, respectively) compared to the healthy control group (4.4% and 26.3%, respectively). Correspondingly, the appearance of the GG genotype was significantly lower in OSAHS patients compared to healthy controls (53.6% vs 69.3%). The A and G allele appeared at a frequency of 27.5% and 72.5% respectively in the OSAHS groups, and 17.6% and 82.4% in the control group respectively.

Conclusions: The distribution of genotypes and alleles of the single nucleotide polymorphism of TNF-α (-308) of OSAHS patients varies from healthy controls.