SCN9A and erythromelalgia: Sensory neurons derived from two patients with inherited erythromelalgia, both carrying the same Nav1.7 mutation but exhibiting different pain levels (mild vs. severe), revealed that neurons from the patient with severe pain were more excitableWhole‐exome sequencing of the pain‐resilient patient uncovered a missense variant in the Kv7.3 channel (KCNQ3), suggesting this variant may play a role in pain resilience