age of onset and disease duration analyses we performed an analysis of variance (ANOVA) with the general linear models procedure in R (www.r-project.org). Independent variables for each ANOVA were the log transformed age of onset or disease duration in years and the individual SNP genotype with additive encoding (ie three categories where 0 is homozygous for the ancestral allele, 1 is heterozygous and 2 is homozygous for the minor allele). Power calculations were based on the rs1990622 allele frequencies observed for cases and controls in the GWAS, using a two-tailed test. We assumed that clinical FTLD cases without TDP-43 pathology as the neuropathological substrate would have allele frequencies similar to controls.
