The strongest increase of nociceptive firing, a predictive of severe migraine pain, was observed for the L263V mutation, likely due to the increased “window current” (Figure 2Aa) because of the shift of the activation in the voltage-dependence curve to lower voltages and the inactivation curve to higher voltages comparing to WT NaV1.1 channels (Kahlig et al., 2008). The gene discussed is SCN1A; the disease is migraine disorder.