Association of Growth Differentiation Factor 5 (GDF5) Gene Polymorphisms with Susceptibility to Knee Osteoarthritis in Saudi Population

Abstract

Background: Osteoarthritis (OA) is among the most prevalent joint diseases. Reduced patient life quality and productivity represent a major personal and community strains. GDF5 gene is involved in the development of bone and cartilage. Studies reported a clear and highly reproducible association between susceptibility of knee osteoarthritis (KOA) and GDF5. This study aims to detect GDF5 gene polymorphism and to evaluate its association with susceptibility to KOA. Methods: This study is a case-control carried out at the female section of College of Applied Medical Sciences, Taif University. 50 Samples with KOA were collected from patients at King Faisal Medical Complex (Rheumatology Clinic), Taif, KSA. The body mass index (BMI) and the functional disability were estimated in all patients. CRP and RF were estimated in the serum of all included subjects by ELISA. ESR was determined by Westergren method. GDF5 T > C (rs143383) promoter polymorphism was assessed by PCRRFLP. Results: We observed a statistically significant elevation of CRP, RF, and ESR on the patients with KOA relative to the controls. Seventy-two percent of our patients have obesity grade I and II and 56% have severe functional disability on Womac index. The TT and TC genotypes of GDF5 gene polymorphism were statistically more frequent in KOA patients than in the controls. TT genotype may be a risk factor to KOA. The T allele was more frequent in KOA and C allele was more frequent in the controls. GDF5 polymorphism was not related to BMI and functional disability of KOA. GDF5 polymorphism was found to be significantly related to high ESR and CRP. Conclusions: The present study revealed a possible genetic link between KOA and GDF5 polymorphism and that the TT genotype may increase the risk of development of KOA. However, a future study with a large number of patients is needed to confirm our results.