Tumor necrosis factor-α gene polymorphism relationship to seminal variables in infertile men

To assess the tumor necrosis factor (TNF)-α gene polymorphism relationship with seminal variables in fertile men (N) and those with asthenozoospermia (A), asthenoteratozoospermia (AT), and oligoasthenoteratozoospermia (OAT).

A total of 50 infertile men without a female factor who were attending a fertility clinic and 48 fertile men were randomly screened for semen analysis, analysis of the TNF-α promoter region for polymorphism, seminal caspase-9, acrosin activity, α-glucosidase, and reproductive hormones.

The TNF-α GG genotype was present in 83.9%, 72.7%, 66.7%, and 59.5%, the TNF-α AA genotype in 3.2%, 6.8%, 10.4%, and 11.9%, and TNF-α AG genotype in 12.9%, 20.5%, 22.9%, and 28.6% in the N, A, AT, OAT groups, respectively. The occurrence of A allele was significantly greater among infertile patients than among fertile controls (21.6% vs 9.7%; odds ratio 0.388, 95% confidence interval 0.2 to 0.75, P = .005). Men with the TNF-α AA genotype demonstrated a significant decrease in the sperm count, sperm motility, normal sperm morphology, acrosin activity, and seminal α-glucosidase and a significant increase in seminal caspase-9 compared with those with the TNF-α GG genotype.

This single nucleotide polymorphism in the TNF-α(-308) gene was associated with significantly increased seminal caspase-9 and a significantly decreased sperm count, sperm motility, normal sperm morphology, acrosin activity, and seminal α-glucosidase.