Mice carrying Kdm5b LoF alleles showed a dose-dependent decrease in spatial memory performance (Barnes maze; two-sided Wald test based on an additive genetic effect with P = 0.012; Kdm5b +/- n = 34 ( P = 0.031) and Kdm5b -/- n = 15 ( P = 0.005) mice spent less time around the goalbox than WT controls, n = 24); showed a dose-dependent decrease in object recognition memory performance (new object recognition; two-sided Wald test based on an additive genetic effect with P = 0.042; Kdm5b +/- n = 32 ( P = 0.038) and Kdm5b -/- n = 15 ( P = 0.011) mice had reduced discrimination compared to WT controls, n = 26); and showed a dose-dependent increase in anxiety-related behavior (light–dark box; two-sided Wald test based on an additive genetic effect with P = 0.008; Kdm5b +/- n = 15 ( P = 0.025) and Kdm5b -/- n = 34 ( P = 0.004) mice spent less time in the light compared to WT controls). P values are based on two-sided Wald tests from a double generalized linear model (dglm v.1.8.5). For the box plot, the center line represents the median, the box limits represent the interquartile range (IQR) and the whiskers indicate the minimum and maximum values. The heatmaps show the relative time spent around various arenas during the trial period of each assay, as a composite of all mice of the same genotype (Barnes maze and light–dark box) or the trace for a single representative animal (new object recognition). Kdm5b +/- (HET) and Kdm5b -/- (HOM) mice spent less time around the goalbox (Barnes maze), showed reduced discrimination of the new object (new object recognition) and spent more time in the dark zone (light–dark box) compared with WT controls.
