In line with the increase in hyperactivity and anxiety noted in our Iqsec2 KO heterozygous females, we observed an increase in total hippocampal volume in heterozygous KO female mice (34%, P = 0.0008 HET versus WT females) and an increase in the volume of the dentate gyrus (48%, P = 0.0006 for HET females) shown in Fig 4D (sections relative to the reference Allen Brain Atlas, Mouse, P56, sagittal images 9–10 of 21). This evidence concerns the gene IQSEC2 and Anxiety.