We conducted two genomewide survival analyses of age at onset in a sample comprising 5148 participants. Similar to the previous analysis, the association signals attained with the genotypes imputed based on the GoNL reference panel were used as input for the gene-based analysis, as these signals were stronger relative to those observed in the 1000G imputed sample (see for a comparison the Manhattan plots, Supplemental Figure S4). As we observed a slight inflation, we corrected the SNP-based P-values (genomic control λ = 1.1171) to prevent potential false positives. Supplemental Figure S5 contains the lambda corrected quantile–quantile plots. The SNP with the strongest association signal was the low-frequency rs142324060 (lambda-corrected P = 7.6 × 10−8; MAF < 5 %). The region around the top SNP associated with initiation—rs142324060 on chromosome 5 is displayed in Supplemental Figure S6. The Supplemental Table S3 contains the top SNPs associated with age at onset (P < 1 × 10−5).
