CNNM2 and epilepsy: Table 3 demonstrates the features of these three types of CNNM2-related disorders. We used one-way ANOVA to compare the initial serum magnesium in patients with three types of CNNM2-related disorders, and no significant difference was found (Figure 2). And we used the Mann–Whitney test to compare the initial serum magnesium in patients with epilepsy and ID/DD (type 2 and type 3) and without epilepsy and ID/DD (type 1); no significant difference was found either (Figure 3).