The authors performed the largest meta-analysis to date on lumbar spine and femoral neck BMD, including 17 genome-wide association studies and 32,961 individuals of European and east Asian ancestry.  They found 56 loci associated with BMD at genome-wide significance of which 32 were new. Several of these clustered within the RANK-RANKL-OPG, mesenchymal stem cell differentiation, endochondral ossification and Wnt signaling pathways. However, they also discovered loci that were localized to genes not known to have a role in bone biology.  In addition fourteen BMD-associated loci were also associated with fracture risk

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