- Ambrosini A, D Onofrio M, Grieco G, Di Mambro A, Montagna G, Fortini D, et al. Familial basilar migraine associated with a new mutation in the ATP1A2 gene. Neurology. 2005;65:1826-8 pubmed..Mutations in CACNA1A and ATP1A2 have been found in FHM. The authors detected a novel mutation in the ATP1A2 gene (R548H) in members of a family with BM, suggesting that BM and FHM may be allelic disorders. ..