An interrupted 34-CAG repeat SCA-2 allele in patients with sporadic spinocerebellar ataxia.
In spinocerebellar ataxia type 2 (SCA-2), a difference of three CAG repeats distinguishes normal alleles (14 to 31 repeats) from pathogenic alleles (34 to 57 repeats). All sequenced pathogenic alleles have a pure CAG repeat structure, whereas interrupted repeats have been seen exclusively in normal alleles. The authors present two patients with sporadic SCA with an interrupted 34-CAG repeat allele, (CAG)24(CAA)(CAG)9, who showed a phenotype compatible with SCA-2. The interrupted allele coding for a 34 pure polyglutamine tract may cause the SCA phenotype.
Costanzi-Porrini
S
S
Department of Neurosciences, San Camillo Hospital, Rome, Italy.
Tessarolo
D
D
Abbruzzese
C
C
Liguori
M
M
Ashizawa
T
T
Giacanelli
M
M
D000368:Aged; D000483:Alleles; D000067528:Ataxins; D001284:Atrophy; D002525:Cerebellar Cortex / Q000473:pathology; D004252:DNA Mutational Analysis; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009419:Nerve Tissue Proteins; D019683:Penetrance; D010641:Phenotype; D011506:Proteins / Q000235:genetics*; D020754:Spinocerebellar Ataxias / Q000235:genetics* / Q000473:pathology; D018911:Trinucleotide Repeats
D000067528:Ataxins; D009419:Nerve Tissue Proteins; D011506:Proteins