TGFBI gene mutations in a Korean population with corneal dystrophy

PURPOSE: To investigate the clinical and genetic features of Korean patients with corneal dystrophies associated with mutations in the human transforming growth factor-β-induced (TGFBI) gene. METHODS: In this study, 387 subjects (71 families and 89 individuals - 268 patients having TGFBI corneal dystrophies and 119 normal relatives) were assessed. All subjects underwent a complete ophthalmologic evaluation, including biomicroscopic inspection and dilated fundus examination. As a control, 100 individuals without corneal disease were selected from the general population. The polymerase chain reaction (PCR) and direct sequencing were used to screen for mutations in TGFBI. RESULTS: All subjects recruited exhibited a range of corneal dystrophies, including Thiel-Behnke corneal dystrophy (TBCD, R555Q; 6 families and 4 individuals), granular corneal dystrophy type 2 (GCD2, R124H; 61 families and 80 individuals), lattice corneal dystrophy (LCD; 4 families and 5 individuals; 7 with type 1 [R124C], and 2 with a variant [L527R, P542R]). The disease showed an autosomal dominant inheritance pattern in all families. CONCLUSIONS: R124H in GCD2 was the most common mutation. GCD1 and Reis-Bucklers corneal dystrophy were not found. In the GCD2 patients there were a large number of laser refractive surgery-induced corneal opacities. A spontaneous R124H mutation was confirmed in an already mutated allele that resulted in a change from a heterozygous into a homozygous form. Also, a novel mutation, P527R, was identified in LCD.