In our finding with CCL2 it has been shown that heterozygous allele AG is more frequent (p = 0.0145) in smoker AMD patients as compared to non-smoker AMD patients, suggesting a causative role of smoking in possible alteration of genetic allele which may lead to differential expression of CCL2 protein in the AMD patients [21]. This evidence concerns the gene CCL2 and age-related macular degeneration.