PPM1H and migraine disorder: Reductions in the expression of adhesion molecules in neurons, such as PPM1H, NTSR2, CLDN10, and CDH13, are related to synaptic N‐methyl‐D‐aspartate (NMDA) receptor‐induced long‐term potentiation69 and affect serotonin (5‐HT) formation, which is potentially relevant to migraine.70, 71