It has been demonstrated that neither plasma PACAP-38 nor VIP exhibited significant changes from baseline levels when CH episodes were induced by CGRP infusion (44).Additionally, plasma CGRP levels remained unchanged during PACAP-38/VIP-induced CH episodes (78), and plasma VIP concentrations similarly yielded negative results (76). The gene discussed is ADCYAP1; the disease is cyclic hematopoiesis.