Congenital hereditary endothelial dystrophy 1 (CHED1) and posterior polymorphous corneal dystrophy 1 (PPCD1) are autosomal-dominant corneal endothelial dystrophies that have been genetically mapped to overlapping loci on the short arm of chromosome 20.
Nine other genes positioned just outside of the common PPCD1 support interval but within the autosomal-dominant congenital hereditary endothelial dystrophy interval were also screened.