Inherited multifocal RPE-diseases: mechanisms for local dysfunction in global retinoid cycle gene defects.
Alterations of retinoid cycle genes are known to cause retinal diseases characterized by focal white dot fundus lesions. Fundus appearances reveal circumscribed RPE-changes, although generalized metabolic defects and global functional abnormalities are present. As a possible explanation, topographic inhomogeneities of the human photoreceptor mosaic and the role of a cone specific visual cycle will be discussed. Due to particular characteristics of photoreceptor subtypes as well as different pathways for photopigment regeneration the metabolic demand of individual RPE cells might differ. In "flecked retina diseases" heterogeneity of metabolic demand in individual RPE cells could therefore be responsible for their multifocal appearance.
Besch
Dorothea
D
University Eye Hospital, Schleichstr. 12-16, D-72076 Tübingen, Germany. dorothea.besch@med.uni-tuebingen.de
Jägle
Herbert
H
Scholl
Hendrik P N
HP
Seeliger
Mathias W
MW
Zrenner
Eberhart
E
D005654:Fundus Oculi; D006801:Humans; D008027:Light; D008268:Macular Degeneration / Q000235:genetics* / Q000503:physiopathology; D009154:Mutation / Q000235:genetics*; D010857:Pigment Epithelium of Eye / Q000502:physiology*; D017949:Retinal Cone Photoreceptor Cells / Q000502:physiology; D012168:Retinal Pigments / Q000378:metabolism; D017948:Retinal Rod Photoreceptor Cells / Q000502:physiology; D012176:Retinoids / Q000378:metabolism; D012177:Retinol-Binding Proteins / Q000172:deficiency; D013577:Syndrome
D012168:Retinal Pigments; D012176:Retinoids; D012177:Retinol-Binding Proteins