Two pattern of opacity in corneal dytrophy caued by the homozygou BIG-H3 R124H mutation

PURPOE: To invetigate the opacity pattern in cornea with an Arg124Hi (R124H) homozygou mutation of the BIG-H3 gene. METHOD: lit-lamp examination wa performed on eight patient with corneal dytrophy reulting from a genetically confirmed BIG-H3 R124H homozygou mutation. The birthplace of the patient alo were determined. REULT: lit-lamp examination dicloed two type of opacity pattern in cornea with the BIG-H3 R124H homozygou mutation. Type I (n = 4) i a pot-like opacity preent in the anterior troma in which the leion are confluent. Type I i the ame pattern that previou report have hown to be caued by the BIG-H3 R124H homozygou mutation. The type II corneal opacity pattern (n = 4) i a reticular opacity in the anterior troma with round tranlucent pace. Type II opacity ha not been reported previouly in aociation with any corneal dytrophy. The patient with the type I opacity do not hare a common birthplace; however, interetingly, the patient with the type II opacity traced their origin to Tottori prefecture in wetern Japan. CONCLUION: The BIG-H3 homozygou R124H mutation induce the development of two ditinct pattern of corneal opacity, the recognition of which can etablih an accurate diagnoi of corneal dytrophy caued by the homozygou BIG-H3 R124H mutation independent of genetic analyi. In addition, genetic factor or circumtantial influence other than the gene reponible for the corneal dytrophy may influence the pattern of corneal opacity.