Analyses of TGFBI gene mutation spectrum in four Chinese families with corneal dystrophy

Abstract

To identify the genetic mutation of TGFBI gene in four Chinese families with corneal dystrophy. The pedigrees were Reis-Bücklers corneal dystrophy (RBCD), Avellino corneal dystrophy (ACD), lattice corneal dystrophy type I(LCDI) and lattice corneal dystrophy type I/IIIA (LCDI/IIIA) (n = 1 each). Genomic DNA was extracted from leukocytes from 22 patients, 22 phenotypic normal family members and 100 normal controls from February 2010 to October 2012. And 17 exons of TGFBI gene were amplified by polymerase chain reaction and sequenced directly. The corneas were examined with slit-lamp biomicroscope and photographed. Mutations of TGFBI gene occurred in all 22 patients, including R124L (c.371G > T) in 14 patients with RBCD, R124H (c.371G > A) mutation in 1 patient with ACD, R124C (c.370C > T) mutation in 3 patients with LCDIand H626R (c.1877A > G) mutation in 4 patients with LCD I/IIIA. The mutations were absent in all participating unaffected family members and normal controls. TGFBI gene-linked corneal dystrophy has close genotype-phenotype relationship. And R124 is a mutant hotspot of TGFBI gene of corneal dystrophy.