Recently, an association between rheumatoid arthritis (RA) and the rs7700944 G>A variant in the T-cell immunoglobulin and mucin domains 4 (TIM-4) has been reported.
The present study aimed at investigating the impact of that polymorphism on susceptibility to RA in a sample of the Iranian population.
This case-control study was conducted on 120 patients with RA and 120 healthy subjects. The rs7700944 polymorphism in the TIM-4 gene was determined using tetra amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) assay.
No significant difference was observed regarding the rs7700944 polymorphism of the TIM-4 gene between patients with RA and normal individuals. In females, no significant association was found between the groups concerning the rs7700944 polymorphism of the TIM-4 gene. In males, the GA+AA genotype increased the risk of RA in comparison with the GG genotype (OR = 5.15, 95% CI = 1.30-20.48, P = 0.020). Furthermore the results showed that the rs7700944 A allele increased the risk of RA (OR = 4.39, 95% CI = 1.43-13.54, P = 0.009).
Our results do not support an association between the rs7700944 polymorphism of the TIM-4 gene and RA. An interaction between this polymorphism and sex suggests a sex-specific association between this single nucleotide polymorphism and RA, which remains to be fully elucidated.