Purpose: To investigate the clinical features and genetic defect in a Chinese family with atypical granular corneal dystrophy type I (GCD I).
Methods: Six patients and four healthy members from the family underwent complete physical and ophthalmologic examination. Genomic DNA samples were obtained from peripheral blood leukocytes of all participated. Exons of the TGFBI gene were directly sequenced after being amplified by polymerase chain reaction (PCR).
Results: Corneal examination revealed multiple bilateral, discrete, crumb-shaped opacities primary in the epithelium , and several in the different depth of corneal stroma , clinical features are quite variable in patients, some of patient only manifest opacities in the epithelium, and the performance of the bilateral corneal in the same person is different. Directly nucleotide sequencing revealed a heterozygous p.R555W mutation in the coding sequence of the transforming growth factor-β-induced(TGFBI) gene in all affected individuals of the family, but was not found in all unaffected.
Conclusions: Our case presented with clinical futures and the pathogenic mutations in TGFBI gene. Opacities of the corneal in this Chinese family primary in the layer of epithelium, with some of patients only manifest opacities in the epithelium, which is different from typical GCD I, so we speculate that this phenotype is a variant of GCD I. This findings expand our knowledge about GCD I, and demonstrate molecular genetic analysis is important to make an accurate diagnosis of patients with variable corneal dystrophies in the clinic.
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