Polymorphism of rs6426749 at 1p36.12 is associated with the risk of osteoarthritis in Taiwanese female population

Background: Osteoarthritis (OA) is a multifactorial disease that is associated with several genetic factors. TFAP2A with a motif of C allele at rs6426749 demonstrates a higher binding ability, thereby increasing CDC42 expression, potentially affecting OA occurrence. In this study, we evaluated the role of rs6426749 polymorphisms on knee OA in a female Taiwanese population. Methods: We performed a case-control study of 368 OA cases and 379 controls between March 2017 and October 2018. Knee OA was defined using the Kellgren-Lawrence grading system, and genotypes were determined using the Sequenom MassArray iPLEX Gold assay. Stratified sex and body mass index (BMI) analyses were performed using logistic regression to explore interactions between genes and the environment. We also used expression quantitative trait loci data from the genotype-tissue expression project to conduct functional analyses. Results: The C allele of rs6426749 was associated with the risk of knee OA (odds ratio [OR] = 1.31, 95% confidence interval [CI], 1.01-1.71; p = 0.042), after adjusting for gender, age, and BMI. In addition, subgroup analyses indicated that females expressing C alleles showed an increased risk for knee OA (OR = 1.56; 95% CI, 1.12-2.18; p = 0.009). Females with a normal BMI and the C allele had the highest OA risk (OR = 1.73; 95% CI, 1.08-2.76; p = 0.022). Conclusion: Our findings indicated that rs6426749 may be related to OA susceptibility in the Taiwanese population. This was particularly true for women with normal BMI.