Association of interleukin-6 gene polymorphisms and circulating levels with keloid scars in a Chinese Han population

The aim of the present study is to explore the effect of IL-6 gene polymorphisms on the development of keloid scar (KS) in the Chinese Han population. Genotyping of IL-6 was performed by the polymerase chain reaction (PCR), followed by restriction fragment length polymorphism assays (PCR-RFLP). Serum level of IL-6 was measured using enzyme-linked immunosorbent assay (ELISA). Results indicated that when the IL-6 -572 CC homozygote genotype was used as the reference group, the GG genotype was found to be associated with a significantly increased risk of KS (GG vs CC: OR = 2.097, 95%CI  = 1.100-3.995, P  =  0.025). When the IL-6 -572 C allele was used as the reference group, the G allele was found to be associated with significantly increased risk of KS (G vs C: OR =  1.317, 95%CI  = 1.002-1.730, P = 0.048). Furthermore, we observed a marked increase in serum IL-6 levels in KS patients with GG genotypes when compared to KS patients harboring the CC genotype. In conclusion, our results suggest that IL-6 gene polymorphism was associated with keloid scars in the southeastern Chinese Han population.