The autosomal-dominant cerebellar ataxias (ADCA) are a heterogeneous group of neurodegenerative disorders characterized by slowly progressive cerebellar dysfunction. Affected individuals have difficulty coordinating body movement, gait ataxia in particular, in addition to other associated findings. Over 17 distinct types of hereditary spinocerebellar ataxia (SCA) disorders have been described. Because of variable expression and phenotypic overlap, the SCA disorders cannot be differentiated reliably on a clinical basis. Although algorithms may predict the likelihood of a specific type of SCA, an accurate diagnosis depends on molecular testing that detects a mutation in a specific causative gene.
The most common types of autosomal dominant spinocerebellar ataxias are SCA1, SCA2, SCA3, SCA6 and SCA7, which are caused by an unstable polymorphic CAG trinucleotid repeat, and SCA8, associated with CTA/CTG expansions.
Adellgene® SCAs is a CE-IVD kit designed for detecting the number of CAG repetitions for SCAs 1, 2, 3, 6 and 7, and CTA/CTG repeats in the case of SCA 8, establishing normal and pathologic ranges of expansions, helping to the clinical diagnosis associated with autosomal dominant SCAs.
The kit is based on the polymerase chain reaction (PCR) technology; the genomic DNA extracted and purified from peripheral blood is amplified and sized by fluorescence analysis in a genetic analyzer. Later, the conversion of this sizing to number of CAG/CTA/CTG is made.