Abstract
Abstract: :
Purpose: To describe characteristic clinical findings of corneal opacity and chronic iritis in 4 cases and to determine mutation of TGFBI(BIGH3) gene of lattice corneal dystrophy. Methods: Case 1: 80 year-old female. Case 2: 48 year old male; son of case 1. Case 3: 52 year-old male; son of case 1. Case 4: 74 year-old female. Clinical findings were evaluated with slit-lamp examination. Genomic DNA was extracted from leukocytes of peripheral blood in case 2,3 and 4. Each 1 to 16 exon of the TGFBI(BIGH3) gene was amplified by polymerase chain reaction (PCR) using each pair of primer and directly sequenced. The PCR products were purified using High Pure PCR Product Purification Kit (Roche Diagnostics GmbH, Mannheim, Germany). After terminator reaction usuing a DNA Sequencing Kit, Dye Terminator Cycle Sequencing, Ready Reaction (Perkin Elmer Applied Biosystems, CA, USA), sequencing was carried out in an automated DNA Sequencer (ABI, Model 373A) in both sense and antisense strands. Results: All of 4 cases demonstrated central diffuse opacity with curly-shaped opacity which is slightly protruded, located in anterior stroma of lower half of the cornea. Curly-shaped opacity might be due to repeated erosion for many years. Typical lattice-shaped filamentary lines were observed from midperiphery to periphery of the cornea. Keratic precipitates with iris pigment were observed in 4 cases. Visual acuity was decreased in all cases (20/600-20/30). Coding region of TGFBI(BIGH3) gene was analyzed by sequencing, however, no mutations were found, even in codons 124, 501, 518, 527, 544, 622, and 626 which are already known as the mutation caused the lattice- type corneal dystrophies. Conclusion: DNA analysis has not detected yet, any mutation in the coding region of TGFBI(BIGH3) gene, however, clinical findings demonstrate new type of lattice corneal dystrophy with characteristic corneal opacity and chronic iritis.
Keywords: 369 cornea: clinical science • 420 genetics • 480 mutations