Six markers localised to the C1q23-C1q31 region covering several genes of interest (ATP1A4, CASQ1, KCNJ9 and J10, FasL and CACNA1E), have been analysed in regard to their potential association with migraine in a large population (243 migraineurs versus 243 healthy individuals). The gene discussed is KCNJ9; the disease is migraine disorder.