Consistent with the findings of previous reports in human tissue,4 analysis of demineralized H&E sections of murine FD lesions revealed increased bone matrix content and decreased cellularity as a result of RANKL inhibition (Fig. 4a), which was associated with a decreased prevalence of Mcm2+ proliferating fibroblasts9 (Fig. 4b). The gene discussed is TNFSF11; the disease is Fabry disease.