These authors investigated whether variants in this gene (associated with Stargardt disease (SD)) contribute to age-related macular degeneration (AMD). The authors found no increased incidence in AMD patients (6/127, 4.7%) or SD patients (4/47, 9.5%) compared to controls (13/80, 16.25%), supporting a nonpathogenic effect.
In fact, this is a significant difference in the other direction — a p=0.0067 for the AMD vs. control set, p = 0.0096 for the combined AMD + SD set. This may mean the control population was not ethnically matched well with the disease cases. Alternatively, the variant could have some protective effect for AMD — the authors do not make this hypothesis, however.