Abstract
Purpose: :
Norrie disease (MIM#310600) is an X-linked disorder characterized by serious vitreoretinal dysplasia at birth. In 1992, the causative gene of Norrie disease, the NDP gene, was isolated. We report NDP gene analysis of three male siblings suspected Norrie Disease.
Methods: :
A seven month new born proband visited our department with leukokoria in both eyes from birth. Bilateral total retinal detachment was observed. His two brothers also visited our department with the same symptoms. Norrie disease was suspected, all three patients being male. For analysis of NDP gene, after obtaining informed consent, DNA was extracted from the peripheral blood of the proband, his one brother, and unaffected mother. Exons 2 and 3 which are cording region of the NDP gene were amplified using the PCR method.
Results: :
Only exon 3 was amplified in the proband and his brother, and two exons were amplified in the mother. Even though PCR primers for exon 2 were changed, the results remained the same. No mutations were observed in PCR products obtained by the direct sequencing method.
Conclusions: :
The three patients were diagnosed with Norrie disease from being male, clinical findings and genetic analysis results. To specify gene carriers and the defective region of the NDP gene, the real-time PCR method and the multiplex ligation-dependent probe amplification (MLPA) method were assumed to be necessary. Of the three male patients suspected of having Norrie disease, two showed abnormalities in the NDP gene. NDP gene analysis is useful for differential diagnosis of Norrie disease.
Keywords: genetics • gene screening • retina