Exploration of Genetic Association Studies with Collagen Variants in Clinically Diagnosed Primary Knee Osteoarthritis in South Indian Population: A Non-replication Study

Osteoarthritis (OA) is the common form of chronic musculoskeletal degenerative joint disease in elder population and earlier studies have correlated the OA with genetics. The aim of this current study was analyse the collagen linked variants such as COL2A1 (rs73297147), CRTL1 (rs73771337), and CRTM (rs74063376) gene polymorphism with clinically diagnosed and radiologically confirmed primary knee osteoarthritis in south Indian population. Two hundred genomic DNA samples were isolated from 100 primary knee OA cases and 100 healthy controls. Genomic DNA was isolated from peripheral blood sample and followed by PCR-RFLP analysis. A significant difference was observed in allele and dominant model in COL2A1 gene polymorphism (G vs A: p=0.01 (OR-1.10-2.48) OR=6.01) and (GG+AG: p=0.001 (OR-1.41-4.74) OR=2.6) within cases and controls. The T allele and TT+GT genotype of CRTL1 gene polymorphism was seen to be a significant difference (G: p=0.005 (OR-1.27-4.64) OR=2.43) and (TT+GT: p=0.01 (OR-1.2-4.74) OR=2.38). The CRTM polymorphism was negatively associated with all alleles and genotypes (p>0.05). GMDR interaction model supports the correlation among these 3 variants. The current results indicate that the rs73297147, rs73771337 polymorphisms in COL2A1 and CRTL1 genes could be associated with developing primary knee OA in south Indian population.