With multivariate analysis considering 65 variables that include previously suggested AMD risk factors of systemic10, 11, 12, 13, genetic7, 19, 20, and environmental factors, we found a strong effect of serum calcium level, ARMS2 A69S genotype, age, and C.pneumonia infection on the development of drusen. The gene discussed is ARMS2; the disease is age-related macular degeneration.