title: Spinocerebellar ataxia type 12 identified in two Italian families may mimic sporadic ataxia.
abstract: SCA12 is an autosomal dominant cerebellar ataxia characterized by onset in the fourth decade of life with action tremor of arms and head, mild ataxia, dysmetria, and hyperreflexia. The disease is caused by an expansion of >or=51 CAGs in the 5' region of the brain- specific phosphatase 2 regulatory subunit B-beta isoform (PPP2R2B) gene. SCA12 is very rare, except for a single ethnic group in India. We screened 159 Italian ataxic patients for SCA12 and identified two families that segregated an expanded allele of 57 to 58 CAGs, sharing a common haplotype. The age at onset, phenotype, and variability of symptoms were compatible with known cases. In one family, the disease was apparently sporadic due to possible incomplete penetrance and/or late age at onset. Our data indicate that SCA12 is also present in Italian patients, and its genetic testing should be applied to both sporadic and familial ataxias.
authors.affiliation: Department of Genetics, Biology and Biochemistry, University of Torino, and S.C.D.U. Medical Genetics, A.O.U. San Giovanni Battista, Torino, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Brussino
authors.forename: Claudio
authors.initials: C
authors.lastname: Graziano
authors.forename: Dario
authors.initials: D
authors.lastname: Giobbe
authors.forename: Marina
authors.initials: M
authors.lastname: Ferrone
authors.forename: Elisa
authors.initials: E
authors.lastname: Dragone
authors.forename: Carlo
authors.initials: C
authors.lastname: Arduino
authors.forename: Raffaele
authors.initials: R
authors.lastname: Lodi
authors.forename: Caterina
authors.initials: C
authors.lastname: Tonon
authors.forename: Anna
authors.initials: A
authors.lastname: Gabellini
authors.forename: Rita
authors.initials: R
authors.lastname: Rinaldi
authors.forename: Sara
authors.initials: S
authors.lastname: Miccoli
authors.forename: Enrico
authors.initials: E
authors.lastname: Grosso
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Bellati
authors.forename: Laura
authors.initials: L
authors.lastname: Orsi
authors.forename: Nicola
authors.initials: N
authors.lastname: Migone
authors.forename: Alfredo
authors.initials: A
authors.lastname: Brusco
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001259:Ataxia / Q000503:physiopathology*; D005192:Family Health; D005260:Female; D006801:Humans; D007558:Italy; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000235:genetics*; D049268:Positron-Emission Tomography / Q000379:methods; D054648:Protein Phosphatase 2 / Q000235:genetics*; D011522:Protons; D012189:Retrospective Studies; D020754:Spinocerebellar Ataxias / Q000175:diagnosis* / Q000235:genetics; D019680:Trinucleotide Repeat Expansion / Q000235:genetics*; D055815:Young Adult
chemical_list: D009419:Nerve Tissue Proteins; D011522:Protons; C505936:PPP2R2B protein, human; D054648:Protein Phosphatase 2