Abstract
Purpose:
To investigate the Leber congenital amaurosis (LCA) and early-onset severe retinal dystrophy (ESRD) phenotypes associated with mutations in RDH12 in Chinese population.
Methods:
Genomic DNA was isolated with standard methods for genetic diagnosis. All 7 exons of RDH12 were amplified with PCR and screened for mutation with direct DNA sequencing. One hundred unrelated healthy Chinese subjects were screened to exclude nonpathogenic polymorphisms. Retinal phenotypes were characterized by ophthalmic examination, including optical coherence tomography (OCT) and standardized electrophysiological tests.
Results:
128 unrelated LCA/ESRD patients were screened for mutations in the RDH12 gene. Homozygous or compound heterozygous RDH12 mutations were found in 12/128 (9.4%) patients, including ten novel mutations and three reported mutations. The petal-like macular coloboma is a characteristic retinal feature related to RDH12 mutation. Marked pigmentary retinopathy, including bone spicules and yellow pin-point pigments in the mid-peripheral retina, was very common in these patients. The OCT showed macular depression and choroiretinal atrophy without normal lamination structure.
Conclusions:
RDH12 is a common cause for LCA/ESRD in Chinese population, with a frequency of 9.4%. The petal-like macular coloboma with dense pigmentation in the peripheral retina may be a characteristic feature related to RDH12 mutation.
Keywords: 533 gene/expression •
696 retinal degenerations: hereditary