INTERLEUKIN-16 RS4778889 POLYMORPHISM AND ITS INTERACTION WITH INTERLEUKIN-10 RS1800896 POLYMORPHISM INCREASE THE RISK FOR KNEE OSTEOARTHRITIS IN THE LEBANESE POPULATION

To investigate the effect Interleukin-16 (IL-16) and Interleukin-10 (IL-10) polymorphisms, and their interaction, on knee osteoarthritis (KOA) risk in the Lebanese population. Kompetitive Allele Specific PCR (KASP) genotyping assay was performed to determine IL-16 rs4778889, rs11556218, and rs4072111 and IL-10 rs1800896 polymorphisms in 118 patients diagnosed with KOA ( ≥ 2 points on Kellgren-Lawrence (K&L) radiological classification scale) and 70 controls matched for age and gender (K&L score ≤ 1). After adjusting for age, gender, presence of metabolic disorders, smoking and drinking status, our findings suggest that rs4778889 TT genotype increases the risk for KOA compared to the combined CC and TC genotypes (OR=2.131, 95% CI 1.037 – 4.379, p = 0.04) and that the T allele increases KOA risk compared to the C allele (OR=1.8, 95% CI 1.008 – 3.212, p = 0.047). No significant associations with the disease risk were found for the other studied polymorphisms (p > 0.05). Our data suggest that there is an interaction between IL-16 rs4778889 and IL-10 rs1800896 (p = 0.010). IL-16 rs4778889 TT genotype increases the risk for KOA only among individuals carrying IL-10 rs1800896 GG or GA genotypes (OR=4.821, 95% CI 1.847 – 12.583). None of the IL-16 haplotypes was associated with KOA risk in our study population (p > 0.05). Our findings suggest that IL-16 rs4778889 T allele is associated with KOA and that there is an interaction between this polymorphism and IL-10 rs1800896 with regard to KOA.