A Simple DNA Chip for Diagnosis of Most Common Corneal Dystrophies Caused by ßigh3 Gene Mutations

The aim of this study is to develop and evaluate a rapid diagnostic DNA chip to detect most common igh3 mutations which cause corneal dystrophies (CDs). Recent studies have shown that LASIK can worsen the CDs, and thus initial screening of igh3 gene mutation is urgently needed before LASIK. Direct sequencing of the exons 4 and 12 of the relevant gene showed that CDs could be mostly divided into homozygous Avellino CD and heterozygous Avellino CD, Heterozygous Lattice Type I, heterozygous Reis-Buckers CD and heterozygous Granular CD. In our previous study, suitable primer and probe sets were designed and DNA chip diagnosing these CDs was successfully developed. Mutations were then identified by signals of the probes immobilized on DNA chip developed and evaluated based on the DNA sequencing results. 327 participants volunteered for this test. Diagnosis was firstly performed by slit-lamp eye examination which is common medical diagnostic method and each DNA sample from peripheral blood was analyzed by DNA chip developed. All the tests were performed as blind tests. The evaluation was finally done by comparing with the DNA sequencing results. We concluded that this rapid genotyping using DNA chip allowed successful detection of CDs with 100% sensitivity and specificity. We thus expect that this simple DNA chip can be a perfect substitute for the routine clinical diagnosis, which will help in making precise diagnoses of patients.