The aims of the study were to establish the prevalence of high bone mass (HBM) in a cohort of Spanish postmenopausal women (BARCOS) and to assess the contribution of LRP5 and DKK1 mutations and of common bone mineral density (BMD) variants to a HBM phenotype. Furthermore, we describe the expression of several osteoblast-specific and Wnt-pathway genes in primary osteoblasts from two HBM cases. A 0.6% of individuals (10/1600) displayed Z-scores in the HBM range (sum Z-score >4). While no mutation in the relevant exons of LRP5 was detected, a rare missense change in DKK1 was found (p.Y74F), which cosegregated with the phenotype in a small pedigree. Fifty-five BMD SNPs from Estrada et al. [NatGenet 44:491-501,2012] were genotyped in the HBM cases to obtain risk scores for each individual. In this small group of samples, Z-scores were found inversely related to risk scores, suggestive of a polygenic etiology. There was a single exception, which may be explained by a rare penetrant genetic variant, counterbalancing the additive effect of the risk alleles. The expression analysis in primary osteoblasts from two HBM cases and five controls suggested that IL6R, DLX3, TWIST1 and PPARG are negatively related to Z-score. One HBM case presented with high levels of RUNX2, while the other displayed very low SOX6. In conclusion, we provide evidence of lack of LRP5 mutations and of a putative HBM-causing mutation in DKK1. Additionally, we present SNP genotyping and expression results that suggest additive effects of several genes for HBM.
References
[1]
Smith DM, Nance WE, Kang KW, Christian JC, Johnston CC Jr (1973) Genetic factors in determining bone mass. J Clin Invest 52: 2800–2808. doi: 10.1172/jci107476
[2]
Cummings SR, Black DM, Nevitt MC, Browner W, Cauley J, et al. (1993) Bone density at various sites for prediction of hip fractures. The Study of Osteoporotic Fractures Research Group. Lancet 341: 72–75. doi: 10.1016/0140-6736(93)92555-8
[3]
Melton LJ 3rd, Atkinson EJ, O'Fallon WM, Wahner HW, Riggs BL (1993) Long-term fracture prediction by bone mineral assessed at different skeletal sites. J Bone Miner Res 8: 1227–1233. doi: 10.1002/jbmr.5650081010
[4]
Gueguen R, Jouanny P, Guillemin F, Kuntz C, Pourel J, et al. (1995) Segregation analysis and variance components analysis of bone mineral density in healthy families. J Bone Miner Res 10: 2017–2022. doi: 10.1002/jbmr.5650101223
[5]
Marshall D, Johnell O, Wedel H (1996) Meta-analysis of how well measures of bone mineral density predict occurrence of osteoporotic fractures. BMJ 312: 1254–1259. doi: 10.1136/bmj.312.7041.1254
[6]
Slemenda CW, Turner CH, Peacock M, Christian JC, Sorbel J, et al. (1996) The genetics of proximal femur geometry, distribution of bone mass and bone mineral density. Osteoporos Int 6: 178–182. doi: 10.1007/bf01623944
[7]
Gong Y, Slee RB, Fukai N, Rawadi G, Roman-Roman S, et al. (2001) LDL receptor-related protein 5 (LRP5) affects bone accrual and eye development. Cell 107: 513–523. doi: 10.1016/s0092-8674(01)00571-2
[8]
Little RD, Carulli JP, Del Mastro RG, Dupuis J, Osborne M, et al. (2002) A mutation in the LDL receptor-related protein 5 gene results in the autosomal dominant high-bone-mass trait. Am J Hum Genet 70: 11–19. doi: 10.1086/338450
[9]
Boyden LM, Mao J, Belsky J, Mitzner L, Farhi A, et al. (2002) High bone density due to a mutation in LDL-receptor-related protein 5. N Engl J Med 346: 1513–1521. doi: 10.1056/nejmoa013444
[10]
Van Wesenbeeck L, Cleiren E, Gram J, Beals RK, Benichou O, et al. (2003) Six novel missense mutations in the LDL receptor-related protein 5 (LRP5) gene in different conditions with an increased bone density. Am J Hum Genet 72: 763–771. doi: 10.1086/368277
[11]
Baron R, Rawadi G (2007) Wnt signaling and the regulation of bone mass. Curr Osteoporos Rep 5: 73–80. doi: 10.1007/s11914-007-0006-0
[12]
Balemans W, Patel N, Ebeling M, Van Hul E, Wuyts W, et al. (2002) Identification of a 52 kb deletion downstream of the SOST gene in patients with van Buchem disease. J Med Genet 39: 91–97. doi: 10.1136/jmg.39.2.91
[13]
Brunkow ME, Gardner JC, Van Ness J, Paeper BW, Kovacevich BR, et al. (2001) Bone dysplasia sclerosteosis results from loss of the SOST gene product, a novel cystine knot-containing protein. Am J Hum Genet 68: 577–589. doi: 10.1086/318811
[14]
Morvan F, Boulukos K, Clement-Lacroix P, Roman Roman S, Suc-Royer I, et al. (2006) Deletion of a single allele of the Dkk1 gene leads to an increase in bone formation and bone mass. J Bone Miner Res 21: 934–945. doi: 10.1359/jbmr.060311
[15]
Gregson CL, Steel SA, O'Rourke KP, Allan K, Ayuk J, et al. (2012) ‘Sink or swim’: an evaluation of the clinical characteristics of individuals with high bone mass. Osteoporos Int 23: 643–654. doi: 10.1007/s00198-011-1603-4
[16]
Gregson CL, Sayers A, Lazar V, Steel S, Dennison EM, et al. (2013) The high bone mass phenotype is characterised by a combined cortical and trabecular bone phenotype: Findings from a pQCT case-control study. Bone 52: 380–388. doi: 10.1016/j.bone.2012.10.021
[17]
Estrada K, Styrkarsdottir U, Evangelou E, Hsu YH, Duncan EL, et al. (2012) Genome-wide meta-analysis identifies 56 bone mineral density loci and reveals 14 loci associated with risk of fracture. Nat Genet 44: 491–501.
[18]
Bustamante M, Nogues X, Mellibovsky L, Agueda L, Jurado S, et al. (2007) Polymorphisms in the interleukin-6 receptor gene are associated with bone mineral density and body mass index in Spanish postmenopausal women. Eur J Endocrinol 157: 677–684. doi: 10.1530/eje-07-0389
[19]
Bustamante M, Nogues X, Agueda L, Jurado S, Wesselius A, et al. (2007) Promoter 2 -1025 T/C polymorphism in the RUNX2 gene is associated with femoral neck BMD in Spanish postmenopausal women. Calcif Tissue Int 81: 327–332. doi: 10.1007/s00223-007-9069-2
[20]
Davis MP, van Dongen S, Abreu-Goodger C, Bartonicek N, Enright AJ (2013) Kraken: a set of tools for quality control and analysis of high-throughput sequence data. Methods 63: 41–49. doi: 10.1016/j.ymeth.2013.06.027
[21]
Little RJA, Rubin DB (1987) Statistical analysis with missing data. New York: John Wiley & Sons.
[22]
Henrotin Y, Pesesse L, Sanchez C (2012) Subchondral bone and osteoarthritis: biological and cellular aspects. Osteoporos Int. 23 (Suppl 8)S847–851. doi: 10.1007/s00198-012-2162-z
[23]
Hilal G, Martel-Pelletier J, Pelletier JP, Ranger P, Lajeunesse D (1998) Osteoblast-like cells from human subchondral osteoarthritic bone demonstrate an altered phenotype in vitro: possible role in subchondral bone sclerosis. Arthritis Rheum 41: 891–899. doi: 10.1002/1529-0131(199805)41:5<891::aid-art17>3.0.co;2-x
[24]
Sanchez C, Deberg MA, Bellahcene A, Castronovo V, Msika P, et al. (2008) Phenotypic characterization of osteoblasts from the sclerotic zones of osteoarthritic subchondral bone. Arthritis Rheum 58: 442–455. doi: 10.1002/art.23159
[25]
Garcia-Moreno C, Mendez-Davila C, de La Piedra C, Castro-Errecaborde NA, Traba ML (2002) Human prostatic carcinoma cells produce an increase in the synthesis of interleukin-6 by human osteoblasts. Prostate 50: 241–246. doi: 10.1002/pros.10050.abs
[26]
Velasco J, Zarrabeitia MT, Prieto JR, Perez-Castrillon JL, Perez-Aguilar MD, et al. (2010) Wnt pathway genes in osteoporosis and osteoarthritis: differential expression and genetic association study. Osteoporos Int 21: 109–118. doi: 10.1007/s00198-009-0931-0
[27]
Ruiz-Gaspa S, Nogués X, Enjuanes A, Monllau JC, Blanch J, et al. (2007) Simvastatin and Atorvastatin enhance gene epression of collagen type 1 and osteocalcin in primary human osteoblasts and MG-63 cultures. J Cell Biochem 101: 1430–1438. doi: 10.1002/jcb.21259
[28]
Duncan EL, Danoy P, Kemp JP, Leo PJ, McCloskey E, et al. (2011) Genome-wide association study using extreme truncate selection identifies novel genes affecting bone mineral density and fracture risk. PLoS Genet 7: e1001372. doi: 10.1371/journal.pgen.1001372
[29]
Brys G, Hubert M, Struyf A (2006) Robust measures of tail weight. Comput Stat Data Anal 50: 733–759. doi: 10.1016/j.csda.2004.09.012
[30]
He X, Semenov M, Tamai K, Zeng X (2004) LDL receptor-related proteins 5 and 6 in Wnt/beta-catenin signaling: arrows point the way. Development 131: 1663–1677. doi: 10.1242/dev.01117
[31]
Zhang Y, Wang Y, Li X, Zhang J, Mao J, et al. (2004) The LRP5 high-bone-mass G171V mutation disrupts LRP5 interaction with Mesd. Mol Cell Biol 24: 4677–4684. doi: 10.1128/mcb.24.11.4677-4684.2004
[32]
Duncan EL, Gregson CL, Addison K, Brugmans M, Pointon JJ, et al. (2009) Mutations in LRP5 and SOST are a rare cause of high bone mass in the general population. Bone 44: S340–S341. doi: 10.1016/j.bone.2009.03.142
[33]
MacDonald BT, Joiner DM, Oyserman SM, Sharma P, Goldstein SA, et al. (2007) Bone mass is inversely proportional to Dkk1 levels in mice. Bone 41: 331–339. doi: 10.1016/j.bone.2007.05.009
[34]
Ke HZ, Richards WG, Li X, Ominsky MS (2012) Sclerostin and Dickkopf-1 as therapeutic targets in bone diseases. Endocr Rev 33: 747–783. doi: 10.1210/er.2011-1060
[35]
Korvala J, Loija M, Makitie O, Sochett E, Juppner H, et al. (2012) Rare variations in WNT3A and DKK1 may predispose carriers to primary osteoporosis. Eur J Med Genet 55: 515–519. doi: 10.1016/j.ejmg.2012.06.011