Our findings reveal that phagolysosomal maturation defects provide the earliest known link between photoreceptoral expression of human mutant ELOVL4 and the onset of photoreceptor cell death, and as such present a potential novel preventative target for STGD3 and other pathologies such as AMD that might share similar triggering events. This evidence concerns the gene ELOVL4 and age-related macular degeneration.