COL2A1 and vitreoretinal degeneration: Finally, the COL2A1 gene encodes collagen type II alpha 1 chain; mutations in this gene can cause Stickler Syndrome Type 1 which is a heterogeneous group of collagen tissue disorders, characterized by orofacial features, and ophthalmological features such as high myopia, vitreoretinal degeneration, retinal detachment, and presenile cataracts56,57.