The Genetic Mysteries of the Corneal Dystrophies The Genetic ...

Posterior Polymorphous Dystrophy• Treatment similar to Fuch’s dystrophy• Mutation is in the COL8A gene in the 20q11locus (long arm of chromosome 20) in somecases• Other cases have mutations in chromosome 1Congenital Hereditary EndothelialDystrophy (CHED 1)• Autosomal dominant• Manifests as diffuse corneal edema a few years afterbirth• May be associated with hearing loss• Photophobia, tearing• Is progressive• Mutation for CHED1 has also been mapped to 20p11-20q11 on chromosome 20-overlaps the location of themutation causing PPD!Congenital Hereditary CornealDystrophy (CHED 2)• Autosomal recessive• Central corneal edema from birth• Nystagmus• Non-progressive but more severe edema thanCHED119