A recent article in Ophthalmology, the most widely-cited eye care scientific journal, reinforces the hypothesis that the genetics of individuals with age-related macular degeneration (AMD) have a major impact on the response to nutritional supplements.  Written by Dr. Carl Awh and colleagues, the published article compares the disease's progression in response to zinc and antioxidant therapies for those who carry certain genetic markers (genotype groups). 
http://dx.doi.org/10.1016/j.ophtha.2014.07.049

Awh CC, Hawken S, Zanke BW:  "Treatment response to antioxidants and zinc based on CFH and ARMS2 genetic risk allele number in the Age-Related Eye Disease Study". Ophthalmology 2015 Jan;122(1):162-9.