Serum concentrations of IL-16 and its genetic polymorphism rs4778889 affect the susceptibility and severity of endometriosis in Nigerian women

Background Endometriosis is the presence of active ectopic endometrial glands and stroma at other sites outside the uterine cavity. It is a common cause of chronic pelvic pain which is sometimes debilitating, and inflammation is one of the known triggers of endometriosis. Interleukins 6 and 16 (IL-6 and IL-16) are proinflammatory cytokines which play essential roles in inflammatory diseases. We therefore investigated the relationship between genetic polymorphisms of interleukins 6 and 16, and the development of endometriosis in Nigerian women. Method One hundred and thirty (130) consenting women were consecutively enrolled, sixty-five (65) of whom had endometriosis and 65 age-matched women as reference group, surgically confirmed as not having endometriosis. Spectrophotometric determination of serum concentrations of Interleukins 6 and 16 was carried out and the genotyping of IL-6 (rs1800795) and IL-16 (rs4778889, rs11556218, rs4072111) genes were performed using TaqMan assays. Results Serum IL-16 concentration was significantly higher in women with severe chronic pelvic pain compared to those with mild pain ( p = 0.023). The C allele of rs4778889 was associated with endometriosis (OR: 1.80, 95% CI: 1.08 – 3.02, p = 0.024). Conclusion Serum IL-16 and IL-16 rs4778889 may be important markers for endometriosis in Nigerian, and by extension, African women. Multicentre African studies would clarify this.