Mutations in type II collagen can also cause a broad range of collagenopathies; for example, COL2A1 (*120140) mutations can lead to achondrogenesis type II (ACG2, #200610), Stickler syndrome (#108300), osteoarthritis with mild chondrodysplasia (OSCDP, #604864), Czech dysplasia (#609162), Kniest dysplasia (#156550), etc. The correlation between the variation of specific type and specific region of this gene and phenotype remains to be fully established. The gene discussed is COL2A1; the disease is Stickler syndrome.