The MN screen results indicating mutants that, compared with the WT, have lower (-MN; left) or higher (+MN; right) MN formation and accumulation. Three statistical tiers are indicated on the basis of P -value cut-offs and false-discovery rates (FDR): tier 1 ( P < 0.001; FDR < 0.017; +MN, red dots; -MN, dark blue dots); tier 2 ( P < 0.005; FDR < 0.046; +MN, orange dots; -MN, blue dots); and tier 3 ( P < 0.01; FDR < 0.068; +MN, yellow dots; -MN, light blue dots). The effect of genotype on the percentage of MN was assessed using a mixed linear effect beta regression model in R with baseline WT mice ( n = 285) together with mice of each genotype. A total of n = 6,210 mice were analysed. Multiple testing was managed by adjusting the P values to control the FDR ( Methods ). The full dataset and statistics are provided in Supplementary Table 1 .
