Knobloch Syndrome 1, also known as retinal detachment and occipital encephalocele, is related to knobloch syndrome and knobloch syndrome 2, and has symptoms including seizures and unspecified visual loss. An important gene associated with Knobloch Syndrome 1 is COL18A1 (Collagen Type XVIII Alpha 1 Chain). Affiliated tissues include eye and bone, and related phenotypes are intellectual disability and nystagmus