The clinical phenotype of oculomotor apraxia type 2 is fairly homogeneous, showing only subtle intrafamilial variability. OMA is an inconstant finding. The identification of new mutations expands the array of SETX variants, and the finding of a missense change outside the helicase domain suggests the existence of at least one more functional region in the N-terminus of senataxin.

HSP-TCC is common in Italy. The phenotype is fairly homogeneous and is associated with impaired cognition. There are at least two loci for HSP-TCC, one of which is on chromosome 15q13-15.

Basilar migraine (BM), familial hemiplegic migraine (FHM), and sporadic hemiplegic migraine (SHM) are phenotypically similar subtypes of migraine with aura, differentiated only by motor symptoms, which are absent in BM. 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.

In this pharmacogenetic study, riboflavin appears to be more effective in patients with migraine with non-H mitochondrial DNA haplotypes. The underlying mechanisms are unknown, but could be related to the association of haplogroup H with increased activity in complex I, which is a major target for riboflavin. Our results may have ethnic implications, since haplogroup H is chiefly found in the European population.

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is an early-onset familial disease with prominent myelinated fibers in the optic fundus. ARSACS is frequent in the Charlevoix-Saguenay region of Quebec but rare elsewhere. Mutations in SACS, encoding sacsin, a protein of unknown function, are associated with ARSACS. The authors identified three new SACS mutations in two Italian patients whose phenotype closely matches that of Quebec cases, but without retinal striation.