Incomplete penetrance in an SPG3A -linked family with a new mutation in the atlastin gene

Ten different spastic gait ( SPG ) loci have been associated with autosomal dominant hereditary spastic paraplegia (ADHSP), and thus far five genes have been identified. Mutations in SPG3A gene encoding atlastin account for ∼10% of ADHSP.1 We report an Italian family with pure ADHSP and incomplete penetrance caused by a new mutation in the atlastin gene (figure). Figure. Tree of the family with SPG3A -linked autosomal dominant hereditary spastic paraplegia. Arrow indicates the proband (IV-10); black and gray symbols represent symptomatic and asymptomatic individuals, respectively, carrying the R415W mutation in the atlastin gene. Symbols with slash mark represent deceased persons. Asterisk indicates patients for whom genetic analysis was performed. Numbers below symbols indicate age at examination. Numbers within symbols indicate two or more family members. Direct sequencing of atlastin gene used reported oligonucleotide primers and the BigDye chemistry (Applied Biosystems, Foster City, CA). A PCR-restriction fragment length polymorphism (PCR-RFLP) method, which uses the endonuclease Msp I (New England Biolabs, Beverly, MA), was used to search for the R415W …