Proportion of carriers of the minor allele according to age in controls free of neurological disease.

SNP = single nucleotide polymorphism. CI = confidence interval. *Chromosomal positions based on the February 2009 (GRCH37/hg19) genome assembly [SNCA is located at Chr4;90,645,251–90,759,447]. P-values result from logistic regression models adjusted for gender, where the outcome was presence of the minor allele of the given SNP, and the predictor variable was age as a continuous variable. Genotype call rates for all SNPs were >95%.