C3 and age-related macular degeneration: Single nucleotide polymorphisms (SNPs), and in some cases rare variants, in the CFH, CFI, CFB, C3, and C9 genes, as well as the complete deletion of the complement factor H-related (CFHR) genes CFHR-1 and CFHR-3, are associated with modifying an individual’s risk of developing AMD [35, 36].