ABSTRACT. Recent data have indicated that inflammation may have an important correlation with obstructive sleep apnea (OSA). Studies have indicated a relationship between OSA and TNF-α gene polymorphisms. Zinc finger protein 36 (ZFP36) regulates TNF-α mRNAs. However, ZFP36 gene polymorphisms have not been investigated in OSA. Therefore, we conducted the present case-control study to assess whether variances in ZFP36 gene polymorphisms account for differences in TNF-α levels in patients with moderate-tosevere OSA. This case-control study aims to investigate the relationship between genetic variations in the ZFP36 gene and moderate-to-severe OSA. Three common single nucleotide polymorphisms of the ZFP36 gene (rs251864, rs3746083, and rs17879933) were evaluated in a group of patients with moderate-to-severe OSA (N = 408) and in a control Y. Zhang et al. 6734©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (2): 6733-6743 (2015) group (N = 394) by using TaqMan polymerase chain reaction analysis. The moderate-to-severe OSA group and the control group exhibited significant differences in the distributions of rs251864 and rs17879933 genotypes and alleles (P < 0.05). TNF-α levels were significantly different not only among the three rs251864 genotypes but also between the II genotype and the DD + ID genotypes of rs17879933. However, no significant differences in sleep apnea parameters in the three ZFP36 gene polymorphisms were observed. Logistic regression analyses demonstrated that TNF-α and the three ZFP36 gene polymorphisms were not independently associated with OSA. ZFP36 might be involved in TNF-α regulation. However, ZFP36 gene variants were not independent risk factors for moderate-to-severe OSA.