CDKL5 and Anxiety: Finally, all these hypoactive lines, except Mecp2−/y, which showed the opposite phenotype, displayed a trend of increased anxiety with either decreased exploration of the centre of the open field during the first 5 min and decreased object exploration (Ehmt1+/−, Ehmt1+/−/Ehmt2+/−) or increased latencies to exit the start arm in the Y-maze (Mbd5+/−, Cdkl5−/y) (Figure 4).