Genotyping and Genetic Risk Scoring

Genotyping was performed as described [10 (link),21 (link)]. Briefly, genomic DNA was extracted from peripheral blood leukocytes by established methods. Genotyping was performed by TaqMan SNP genotyping (Applied Biosystems, Foster City, USA) or by PCR followed by restriction enzyme digestion (New England Biolabs, Ipswich, USA) and subsequent restriction fragment length analysis (RFLP).The resulting genotypes were coded as the number of AMD risk increasing alleles (0, 1 or 2), i.e. alleles which are more frequent in cases than in controls (S1 Table) [21 (link)]. These variants were used to compute the genetic risk score according to Grassmann et al. 2012 with weights obtained from the parsimonious model based on 10 SNPs (S1 Table).