Large pathogenic expansions in the SCA2 and SCA7 genes can be detected by fluorescent repeat-primed polymerase chain reaction assay.
Large expansions in the SCA2 and SCA7 genes (>100 CAG repeats) have been associated with juvenile and infantile forms of cerebellar ataxias that cannot be detected using standard polymerase chain reaction (PCR). Here, we describe a successful application of the fluorescent short tandem repeat-primed PCR method for accurate identification of these expanded repeats. The test is robust, reliable, and inexpensive and can be used to screen large series of patients, although it cannot give a precise evaluation of the size of the expansion. This test may be of practical value in prenatal diagnoses offered to affected or pre-symptomatic at-risk parents, in which a very large expansion inherited from one of the parents can be missed in the fetus by standard PCR.
Cagnoli
Claudia
C
Dipartimento di Genetica Biologia e Biochimica, Università degli Studi di Torino, via Santena 19, 10126, Torino, Italy.
Stevanin
Giovanni
G
Michielotto
Chiara
C
Gerbino Promis
Giovanni
G
Brussino
Alessandro
A
Pappi
Patrizia
P
Durr
Alexandra
A
Dragone
Elisa
E
Viemont
Michelle
M
Gellera
Cinzia
C
Brice
Alexis
A
Migone
Nicola
N
Brusco
Alfredo
A
D000067719:Ataxin-7; D000067528:Ataxins; D016022:Case-Control Studies; D005453:Fluorescence; D006580:Genetic Carrier Screening; D005820:Genetic Testing; D006801:Humans; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods*; D013132:Spinocerebellar Degenerations / Q000175:diagnosis* / Q000235:genetics; D019680:Trinucleotide Repeat Expansion / Q000235:genetics*
C000593829:ATXN7 protein, human; D000067719:Ataxin-7; D000067528:Ataxins; D009419:Nerve Tissue Proteins