RANK (receptor activator of nuclear factor-kappa B), encoded by TNFRSF11A, is a key protein in osteoclastogenesis TNFRSF11A mutations cause Paget's disease of bone (PDB)-like diseases (ie, familial... Show moreRANK (receptor activator of nuclear factor-kappa B), encoded by TNFRSF11A, is a key protein in osteoclastogenesis TNFRSF11A mutations cause Paget's disease of bone (PDB)-like diseases (ie, familial expansile osteolysis, expansile skeletal hyperphosphatasia, and early-onset PDB) and an osteoclast-poor form of osteopetrosis However, no TNFRSF11A mutations have been found in classic PDB, neither in familial nor in isolated cases To investigate the possible relationship between TNFRSF11A polymorphisms and sporadic PDB, we conducted an association study including 32 single-nucleotide polymorphisms (SNPs) in 196 Belgian sporadic PDB patients and 212 control individuals Thirteen SNPs and 3 multimarker tests (MMTs) turned out to have a p value of between 036 and 317 x 10(-4), with the major effect coming from females Moreover, 6 SNPs and 1 MMT withstood the Bonferroni correction (p < 002) Replication studies were performed for 2 nonsynonymous SNPs (rs35211496 and rs1805034) in a Dutch and a British cohort Interestingly, both SNPs resulted in p values ranging from 013 to 838 x 10(-5) in both populations Meta-analysis over three populations resulted in p = 002 for rs35211496 and p = 1 27 x 10(-8) for rs1805034, again mainly coming from the female subgroups In an attempt to identify the underlying causative SNP, we performed functional studies for the coding SNPs as well as resequencing efforts of a 31-kb region harboring a risk haplotype within the Belgian females However, neither approach resulted in significant evidence for the causality of any of the tested genetic variants Therefore, further studies are needed to identify the real cause of the increased risk to develop PDB shown to be present within TNFRSF11A (C) 2010 American Society for Bone and Mineral Research Show less
Chung, P.Y.J.; Beyens, G.; Boonen, S.; Papapoulos, S.; Geusens, P.; Karperien, M.; ... ; Hul, W. van 2010
Paget's disease of bone (PDB) is one of the most frequent metabolic bone disorders (1-5%), next to osteoporosis, affecting individuals above age 55. Sequestosome1 mutations explain a part of the... Show morePaget's disease of bone (PDB) is one of the most frequent metabolic bone disorders (1-5%), next to osteoporosis, affecting individuals above age 55. Sequestosome1 mutations explain a part of the PDB patients, but still the disease pathogenesis in the remaining PDB patients is largely unknown. Therefore, association studies investigating the relationship between genetic polymorphisms and sporadic PDB have been performed to find the genetic risk variants. Previously such studies indicated a role of the OPG and RANK gene. The latter was recently confirmed in a genome-wide association study (GWAS) which also indicated the involvement of chromosomal regions harbouring the CSF1 and OPTN gene. In this study, we sought to replicate these findings in a Belgian and a Dutch population. Similar significant results were obtained for the single nucleotide polymorphisms and the haplotypes. The most significant results are found in the CSF1 gene region, followed by the OPTN and TNFRSF11A gene region (p values ranging from 1.3 x 10(-4) to 3.8 x 10(-8), OR = 1.523-1.858). We next obtained significant association with a polymorphism from the chromosomal region around the TM7SF4 gene (p = 2.7 x 10(-3), OR = 1.427), encoding DC-STAMP which did not reach genome-wide significance in the GWAS, but based on its function in osteoclasts it can be considered a strong candidate gene. After meta-analysis with the GWAS data, p values ranged between 2.6 x 10(-4) and 8.8 x 10(-32). The calculated cumulative population attributable risk of these four loci turned out to be about 67% in our two populations, indicating that most of the genetic risk for PDB is coming from genetic variants close to these four genes. Show less