Geographical feature of lattice corneal dystrophy patients in Aichi Prefecture: an analysis of the TGFBI gene

PURPOSE: To investigate the genetics of patients with lattice corneal dystrophy (LCD) in Aichi Prefecture, the majority of whom originated from the same area of Hazu-gun. METHODS: We studied twenty patients who visited Nagoya University Hospital from April 1997 to March 2000 and were diagnosed as having LCD. A complete history including a detailed family history was obtained from each of the patients. DNA analysis was performed on each patient with an informed consent. RESULTS: Fourteen patients had an obvious family history, and 7 pedigrees were detected. Four of the 7 families were from Hazu-gun, and Arg 124 Cys mutation in the TGF-beta indused gene human 3(TGFBI) gene was detected in the families. A family from Nishikasugai-gun had a Leu 518 Pro mutation in the same gene. Six patients were considered sporadic without any family history. However, a heterozygous single base-pair transition (leucine to arginine) was detected in codon 527 of the TGFBI gene in 4 out of these 6 patients. CONCLUSION: Genetic analysis confirmed that LCD observed in patients from Hazu-gun is a type I LCD caused by an Arg 124 Cys mutation in the TGFBI gene. TGFBI gene mutations, other than the Arg 124 Cys, were detected in a family with LCD type I in Aichi Prefecture. Among the autosomal dominant inherited LCDs, there is at times a sporadic pattern because of its late-onset form.