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

Summary of the Molecular Genetics of theCorneal Dystrophies• Meesmann’s• KRT 3, KRT 12 genes onchromosomes 12, 17• Lisch (Whorled)• Unidentified gene on Xchromosome• Reis-Buckler’s Granular Type III)• TGFBI gene on chromosome 5• Granular Dystrophy• TGFBI chromosome 5• Lattice I,III,IV, V, VI, etc.• TGFBI,chromosome 5• Lattice II• GSN,chromosome 9• Macular Dystrophy• CHST6 gene,chromosome 16• Crystalline Dystrophy• Gene ? chromosome 1• Fuch’s Dystrophy• PPD and CHED• COL8A gene on chromosome20• Chromosome 1Courtesy: Redatlas.orgConsider Classification by AffectedChromosomeImplications of Molecular Geneticsfor the Future• Chromosome 1 Dystrophies• Central crystalline dystrophy• Early onset Fuch’s dystrophy• Posterior polymorophous dyst• Chromosome 2 Dystrophies• Fleck dystrophy• Chromosome 5 Dystrophies• Lattice dystrophy (Types 1 andIIIA)• Granular dystrophy• Avellino dystrophy (GCDII)• Reis-Buckler’s dystrophy (GCDIII)• Chromosome 9 Dystrophies• Lattice dystrophy Type II• Chromosome 12 Dystrophies• Meesman dystrophy (and 17)• Chromosome 16 Dystrophies• Macular corneal dystrophy• Chromosome 20 Dystrophies• Congenital Hereditary EndothelialDystrophy Types I and II• Posterior Polymorphous Dyst• Chromosome 21 Dystrophies• A/D Keratoconus• X-chromosome Dystrophies• Lisch corneal dystrophy• Knowledge of mutations enables researchers toidentify the pathways that synthesize abnormalproteins which are deposited in the cornea• This knowledge can lead to the development ofnew drugs designed to interfere with thesepathways to decrease abnormal proteinsynthesis• Less deposition = less affect on vision = less Tx20