July 13 Highlights

Hedera et al. (p. 44) describe the phenotype of hereditary spastic paraplegia (HSP) linked to chromosome 8q23-24.Other than increased severity, no clinical features distinguished the family they describe from those with autosomal dominant HSP linked to other chromosomes.The authors question whether the multiple genes responsible for these clinically indistinguishable disorders involve a common biochemical cascade.Mitochondrial disturbance, postulated to be a common factor of HSP, is not a feature of the new gene.characterize a new and apparently common gene locus for recessive familial spastic paraparesis linked to chromosome 15q.In their accompanying editorial, Figlewicz and Bird (p. 5) review the genetics of HSP and highlight the critical issues that must be settled.᭜ Three articles and the editorial by Tournier-Lasserve (p. 3) relate to CACNA1A mutations.Jen et al. (p.34) describe a nonsense mutation in the gene that causes episodic ataxia and weakness as well as episodic hemiplegia with or without migraine.Battistini et al. (p.38) performed lineage analysis of the CACNA1A gene in two siblings who experienced typical hemiplegic migraine attacks, sometimes associated with altered consciousness and fever.Both individuals also experienced a permanent, late onset, cerebellar ataxia with cerebellar atrophy.Acetazolamide effectively treated the episodic symptoms but had no effect on the progressive ataxia.The authors speculate that the combination of episodic and permanent deficits could depend on the variety of functions of calcium channels and their distribution in the nervous system.Carrera et al. (p.26) studied Italian families with