Some variants in exon 2 of COL2A1 are often associated with Stickler syndrome, such as c.G170>A (p. Cys57Tyr) and c.G192>A (Cys64Stop), and these variants result in a shift in alternative splicing pattern towards the IIB isoform, which causes a lower ratio of IIA/IIB.12 Here, COL2A1 is linked to Stickler syndrome.