The TMJ OA is a degenerative disease with age-related joint disorder.25 Meanwhile, TMJ disorders mostly affect young women according to recent researches.26,27 The Agc1-CreERT2 transgenic mouse model is a valuable tool to investigate the postnatal OA development, allowing chondrocyte-specific gene targeting in an inducible manner.24 To determine the role of β-catenin in TMJ OA development in postnatal mice, we decided to induce β-catenin expression in 2-week-old mice. The gene discussed is ACAN; the disease is neurodegenerative disease.