Specifically, confocal microscopy analyses of retina sections and RPE wholemounts showed increased autofluorescence material/debris accumulation in the photoreceptor layer and reduced autofluorescence in RPE cells from CLN3 disease donor eyes compared to RPE autofluorescence in non-CLN3 donor eyes, an age-matched donor eye with Charcot Marie Tooth Disease and adult healthy control donor eye (Fig. 2A, B; Supplementary Fig. 2). Here, CLN3 is linked to glycogen storage disease VI.