SQSTM1 and Paget disease: In humans, the p62 mutation is observed in ~40%–50% of patients with Paget’s bone disease (PD), a condition involving increased bone resorption by osteoclasts, followed by excessive and disorganized bone formation by osteoblasts.170 This phenotype has also been recapitulated in mice, where a mutation in the gene Sqstm1 encoding the p62 protein results in excessive osteoclastic activity and a phenotype similar to Paget’s disease.171