Although having the mutation more than doubles a person's risk of the disorder, which causes loss of central vision, it doesn't mean that person will automatically develop the disorder. (discovermagazine.com)
Central vision loss also occurs, while peripheral vision usually is retained. (allaboutvision.com)
This leakage causes permanent damage to light - sensitive retinal cells, which die off and create blind spots in central vision. (allaboutvision.com)