The specific involvement of Axin/β-catenin in the onset and progression of SYNS remains uncertain.85, 86, 87, 88, 89 It was also reported that deletion of Axin1 results in many other bone deformities, such as cartilage defects,20 the osteoarthritis-type phenotype in the temporomandibular joint,21 and defects in postnatal bone growth.90 The gene discussed is AXIN1; the disease is osteoarthritis.