Common variants in the GNL3 contribute to the increasing risk of knee osteoarthritis in Han Chinese population
SCIENTIFIC REPORTS
Authors: Liu, Bo; Chang, Huiguang; Ma, Wenlong; Gong, Futai; Wang, Xiangyang; Duan, Ning; Dang, Xiaoqian
Abstract
Osteoarthritis (OA) is a complex degenerative joint disorder, which is caused by both environmental and genetic factors. Previous studies have indicated that the GNL3 gene is associated with knee osteoarthritis (KOA) susceptibility in Europeans; however, the exact molecular mechanism is still unclear. In the present study, we investigated the potential genetic association of GNL3 with KOA in a two-stage sample of 6,704 individuals from the Han Chinese population. Subjects containing 1,052 KOA patients and 2,117 controls were considered the discovery dataset, while subjects consisting of 1,173 KOA patients and 2,362 controls were utilized as the replication dataset. Single-SNP association, imputation, and haplotypic association analyses were performed. The SNP of rs11177 in GNL3 was identified to be significantly associated with KOA after accounting for age, gender and BMI in both stages. The imputed SNP of rs6617 in SPCS1 was found to be strongly associated with KOA risk, and the significant association signal was confirmed in the replication stage. Moreover, a haplotype-based analysis also indicated a positive genetic effect of GNL3 on KOA susceptibility. In summary, our results proved that GNL3 plays an important role in the etiology of KOA, suggesting that GNL3 is a potential genetic modifier for KOA development.
Identification of new susceptibility loci for osteoarthritis (arcOGEN): a genome-wide association study
LANCET
Authors: Zeggini, Eleftheria; Panoutsopoulou, Kalliope; Southam, Lorraine; Rayner, Nigel W.; Day-Williams, Aaron G.; Lopes, Margarida C.; Boraska, Vesna; Esko, Tonu; Evangelou, Evangelos; Hofman, Albert; Houwing-Duistermaat, Jeanine J.; Ingvarsson, Thorvaldur; Jonsdottir, Ingileif; Jonsson, Helgi; Kerkhof, Hanneke J. M.; Kloppenburg, Margreet; Bos, Steffan D.; Mangino, Massimo; Metrustry, Sarah; Slagboom, P. Eline; Thorleifsson, Gudmar; Raine, Emma V. A.; Ratnayake, Madhushika; Ricketts, Michelle; Beazley, Claude; Blackburn, Hannah; Bumpstead, Suzannah; Elliott, Katherine S.; Hunt, Sarah E.; Potter, Simon C.; Shin, So-Youn; Yadav, Vijay K.; Zhai, Guangju; Sherburn, Kate; Dixon, Kate; Arden, Elizabeth; Aslam, Nadim; Battley, Phillippa-Kate; Carluke, Ian; Doherty, Sally; Gordon, Andrew; Joseph, John; Keen, Richard; Koller, Nicola C.; Mitchell, Sheryl; O'Neill, Fiona; Paling, Ellen; Reed, Mike R.; Rivadeneira, Fernando; Swift, Diane; Walker, Kirsten; Watkins, Bridget; Wheeler, Maggie; Birrell, Fraser; Ioannidis, John P. A.; Meulenbelt, Ingrid; Metspalu, Andres; Rai, Ashok; Salter, Donald; Stefansson, Kari; Styrkarsdottir, Unnur; Uitterlinden, Andre G.; van Meurs, Joyce B. J.; Chapman, Kay; Deloukas, Panos; Ollier, William E. R.; Wallis, Gillian A.; Arden, Nigel; Carr, Andrew; Doherty, Michael; McCaskie, Andrew; Wilkinson, J. Mark; Ralston, Stuart H.; Valdes, Ana M.; Spector, Tim D.; Loughlin, John
Abstract
Background Osteoarthritis is the most common form of arthritis worldwide and is a major cause of pain and disability in elderly people. The health economic burden of osteoarthritis is increasing commensurate with obesity prevalence and longevity. Osteoarthritis has a strong genetic component but the success of previous genetic studies has been restricted due to insufficient sample sizes and phenotype heterogeneity. Methods We undertook a large genome-wide association study (GWAS) in 7410 unrelated and retrospectively and prospectively selected patients with severe osteoarthritis in the arcOGEN study, 80% of whom had undergone total joint replacement, and 11 009 unrelated controls from the UK. We replicated the most promising signals in an independent set of up to 7473 cases and 42 938 controls, from studies in Iceland, Estonia, the Netherlands, and the UK. All patients and controls were of European descent. Findings We identified five genome-wide significant loci (binomial test p <= 5.0x10(-8)) for association with osteoarthritis and three loci just below this threshold. The strongest association was on chromosome 3 with rs6976 (odds ratio 1.12 [95% CI 1.08-1.16]; p=7.24x10(-11)), which is in perfect linkage disequilibrium with rs11177. This SNP encodes a missense polymorphism within the nucleostemin-encoding gene GNL3. Levels of nucleostemin were raised in chondrocytes from patients with osteoarthritis in functional studies. Other significant loci were on chromosome 9 close to ASTN2, chromosome 6 between FILIP1 and SENP6, chromosome 12 close to KLHDC5 and PTHLH, and in another region of chromosome 12 close to CHST11. One of the signals close to genome-wide significance was within the FTO gene, which is involved in regulation of bodyweight-a strong risk factor for osteoarthritis. All risk variants were common in frequency and exerted small effects. Interpretation Our findings provide insight into the genetics of arthritis and identify new pathways that might be amenable to future therapeutic intervention.