Development of a DNA chip for the diagnosis of the most common corneal dystrophies caused by mutations in the betaigh3 gene.
OBJECTIVE
To develop a diagnostic DNA chip to detect mutations in the betaigh3 gene causing the most common corneal dystrophies (CDs).


METHODS
Samples from 98 people, including patients with betaigh3-associated CDs (beta-aCDs), were examined. Specific primer and probe sets were designed to examine exons 4 and 12 of the betaigh3 gene, in order to identify mutant and wild-type alleles. Mutations were then identified by hybridisation signals of sequence-specific probes immobilised on the slide glass.


RESULTS
Direct sequencing of exons 4 and 12 of the betaigh3 gene in the patients' genome showed that beta-aCDs could be mainly classified into five types: homozygotic Avellino corneal dystrophy (ACD), heterozygotic ACD, heterozygotic lattice CD I, heterozygotic Reis-Bucklers CD and heterozygotic granular CD. Blind tests were performed by applying the target DNA amplified from the genomic DNA isolated from the peripheral blood of the participants onto a DNA chip. The results obtained by DNA chip hybridisation matched well with the direct DNA sequencing results.


CONCLUSIONS
The DNA chip developed in this study allowed successful detection of beta-aCDs with a sensitivity of 100%. Mutational analysis of exons 4 and 12 of the betaigh3 gene, which are the mutational hot spots causing beta-aCDs, can be successfully performed with the DNA chip. Thus, this DNA chip-based method should allow a convenient, yet highly accurate, diagnosis of beta-aCDs, and can be further applied to diagnose other types of CDs.
Yoo
So Young
SY
Department of Chemical and Biochemical Engineering, Korea Advanced Institute of Science and Technology (KAIST), 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea.
Kim
Tae-Im
TI
Lee
Sang Yup
SY
Kim
Eung Kweon
EK
Keum
Ki Chang
KC
Yoo
Nae Choon
NC
Yoo
Won Min
WM
D001483:Base Sequence; D003317:Corneal Dystrophies, Hereditary / Q000175:diagnosis* / Q000235:genetics; D004252:DNA Mutational Analysis / Q000379:methods; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D005136:Eye Proteins / Q000235:genetics*; D006801:Humans; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D012680:Sensitivity and Specificity; D016212:Transforming Growth Factor beta / Q000235:genetics*; D000099222:betaIG-H3 Protein
D016326:Extracellular Matrix Proteins; D005136:Eye Proteins; D016212:Transforming Growth Factor beta; D000099222:betaIG-H3 Protein