Association of TCF7L2 and LEPR gene variants (rs7903146 and rs1137101) with primary knee osteoarthritis in a northern Mexican Mestizo population

INTRODUCTION: There is a growing interest in the study of Obesity, Diabetes, and their genetic polymorphisms for the risk of developing osteoarthritis. This study analyzed the associations among the rs1137101 LEPR gene and rs7903146 polymorphisms TCF7L2 gene with primary knee osteoarthritis in a population from northern Mexico. METHODS: We conducted a case-control study with 438 Mexican Mestizo participants, selected non-randomly by convenience. We included age, diabetes, and body mass index for analysis. The presence of the TCF7L2 (n = 236) and LEPR (n = 405) gene genotypes was determined using real-time PCR with the rhAmpTM SNP Assay methodology. We performed comparisons between groups using the chi-square test, Fisher´s exact test, the Mann-Whitney U test, and adjusted regression model analysis. RESULTS: The CC genotype of the rs7903146 ​​polymorphism was significantly associated as risk factor with obesity (p = 0.043; OR 2.021, CI 1.023 - 3.989) and CT genotype as a protective factor (p = 0.016, p = 0.013, and p = 0.008); the CC genotype was significantly associated with primary KOA as a risk factor (p = 0.040; OR 2.061, CI 1.034 - 4.107) and the CT genotype as a protective factor (p = 0.039, and p = 0.041; OR 0.480, CI 0.237 - 0.970). No association was found between the genotypes for LEPR rs1137101 and KOA. CONCLUSION: This study suggests a possible role for the rs7903146 ​​polymorphism of the TCF7L2 gene, in the risk of primary KOA and obesity. We suggest conducting additional studies with a larger population sample, including other polymorphisms of the same genes in different ethnic groups, to corroborate the findings shown in this study. Key Points • We observed significant associations for obesity and primary knee osteoarthritis in the presence of the rs7903146 CC and CT genotypes.