A Role for Heterozygosity of NF-𝜠B1 rs28362491 Polymorphism in Patients with Idiopathic Oligospermia.

BACKGROUND: Nuclear factor-kappa B (NF-𝜅B) activation and its inhibition by NF-𝜅B inhibitor (I𝜅B) have been functionally linked to germ cell apoptosis, which may affect human infertility. We hypothesized a possible relationship between the NF-𝜅B1-94ins/del ATTG (rs28362491) and NF-𝜅BIA 3'UTR A→G (rs696) polymorphism, which are common polymorphisms and the susceptibility to oligospermia in the context of the sperm apoptosis. METHODS: In order to evaluate this association, we studied the polymorphisms and sperm apoptosis rates of 114 men with idiopathic oligospermia, as well as 130 normospermic men, using PCR-RFLP and TUNEL staining methods, respectively. RESULTS: Univariate analysis revealed that heterozygous ID genotype at the NF-𝜅B1 -94ins/del ATTG polymorphism is associated with an approximately 2.4-fold reduced risk of oligospermia (P = 0.006, 95% confidence intervall = 1.34 - 4.13). However, the genotype and allele frequencies of NF-𝜅BIA 3'UTR A→G polymorphism, and the genotype frequencies of all possible rs28362491/rs696 genotype combinations did not show any significant differences between oligospermic and normospermic men. Furthermore, neither polymorphism appeared to affect sperm apoptosis, although the sperm apoptosis index was detected to be significantly higher in the oligospermic patients compared with those in the controls (P < 0.05). CONCLUSION: Our findings suggested that the heterozygosity of rs28362491 in the NF-𝜅B1 gene may have a protective effect against oligospermia and could modify the susceptibility of oligospermia in a group with idiopathic male infertility in a Turkish population.