Novel Heterozygous Deletion in Retinol Dehydrogenase 12 (RDH12) Causes Familial Autosomal Dominant Retinitis Pigmentosa.

Hajrah Sarkar,Adam M Dubis,Mariya Moosajee,Susan Downes

doi:10.3389/fgene.2020.00335

Abstract

Mutations in the retinol dehydrogenase 12 (RDH12) gene are primarily associated with Leber congenital amaurosis (LCA) type 13, a severe early onset autosomal recessive retinal dystrophy. Only one family with a heterozygous variant, associated with mild retinitis pigmentosa (RP), has been reported. We report a novel heterozygous variant [(c.759del; p.(Phe254Leufs∗24)], resulting in a frameshift and premature termination identified in two unrelated individuals with familial autosomal dominant RP. Both heterozygous variants are associated with a late onset RP phenotype, suggesting a possible genotype-phenotype correlation.

Highlights

Retinol dehydrogenase 12 (RDH12) is an NADPH-dependent retinal reductase that catalyzes the reduction of all-trans retinal to all-trans retinol, and is expressed in photoreceptor inner segments (Belyaeva et al, 2005)
The comparison is further made by the presence of the classic retinitis pigmentosa (RP) autofluorescent ring pattern compared to the much more variegated pattern in previous RDH12 reports (Kumaran et al, 2017; Aleman et al, 2018)
Eighty RDH12 mutations have been reported to date, 64% of which are missense, 15% are nonsense and 14% are small insertions or deletions, including 6 autosomal recessive deletions associated with the severe early onset Leber congenital amaurosis (LCA) phenotype (HGMD public database accessed August 2019)

Summary

Introduction

Retinol dehydrogenase 12 (RDH12) is an NADPH-dependent retinal reductase that catalyzes the reduction of all-trans retinal to all-trans retinol, and is expressed in photoreceptor inner segments (Belyaeva et al, 2005). We describe two unrelated individuals with autosomal dominant RP associated with a novel point deletion in RDH12 with a similar phenotype. His best corrected visual acuity with LogMAR was 0.04 in both eyes, fundus examination showed mild waxy disc pallor with retinal vessel attenuation and mid-peripheral bone-spicules.

Results

Conclusion