Candidate Gene Association Study of Magnetic Resonance Imaging-based Hip Osteoarthritis (OA): Evidence for COL9A2 Gene as a Common Predisposing Factor for Hip OA and Lumbar Disc Degeneration

Objective. To study whether gene variants associated with lumbar disc degeneration (LDD) phenotypes are also associated with hip osteoarthritis (OA). Methods. Magnetic resonance imaging (MRI)-based hip OA changes for 345 twins were assessed and 99 single-nucleotide polymorphisms (SNP) were analyzed. Results. Variants in the COL9A2 (rs7533552, p = 0.0025) and COL10A1 (rs568725, p = 0.002) genes showed association with hip OA. Conclusion. The associating G allele in COL9A2 changes a glutamine to arginine or to tryptophan and may predispose to both hip OA and LDD, making it a candidate for degenerative connective tissue diseases. (First Release Dec 15 2010; 3 Rheumatol 2011;38:747-52; doi:10.3899/jrheum.100080)