RDH5 and fundus albipunctatus: During a phenotype screen in KO mice, fundoscopy of 12- to 16-week-old AdipoR1 KO mice revealed a flecked retinal syndrome resembling human fundus albipunctatus, which is associated with a recessive mutation in 11-cis-retinol dehydrogenase (RDH5), the enzyme that converts 11-cis-retinol into 11-cis-retinal in the retinoid cycle14, 15.