Growth differentiation factor 5 (GDF5) core promoter polymorphism is not associated with susceptibility to osteoarthritis of the knee in the Korean population

Background: Osteoarthritis (OA) is a common disease characterized by degenerating joint cartilage in the knee, hip, and hand. A functional single nucleotide polymorphism (SNP) +104-T/C; rs143383 in the 5′untranslated region of the growth differentiation factor 5 (GDF5) gene was recently associated with susceptibility to OA in the Japanese and Chinese populations. Methods: To investigate whether this association is present in the Korean population, the frequency of the polymorphism was investigated in 276 patients with knee OA and 298 healthy subjects as controls. Polymorphism analysis was performed by amplifying the core promoter region of the GDF5 gene and digesting it with the BsiEI restriction enzyme. Results: The frequency of the TT, CT, and CC genotypes was 54.3% (150/276), 41.7% (115/276), and 4.0% (11/276), respectively, in patients with OA, and 53.4% (159/298), 37.9% (113/298), and 8.7% (26/298), respectively, in healthy controls. No significant differences in genotypic or allelic frequencies of the +104T/C SNP of the GDF5 gene were observed between patients with OA and controls. Also, no significant differences in allelic and genotypic frequencies were found when the individuals were stratified by age and gender. Conclusions: The results suggest that the +104T/C; rs143383 GDF5 core promoter polymorphism is not a risk factor for OA in the Korean population.