Factors associated with ATXN2 CAG/CAA repeat intergenerational instability in Spinocerebellar ataxia type 2.
Spinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disorder caused by the unstable expansion of a cytosine-adenine-guanine (CAG)/cytosine-adenine-adenine (CAA) repeat in the ATXN2 gene, which normally encodes 22 glutamines (Q22). A large study was conducted to characterize the CAG/CAA repeat intergenerational instability in SCA2 families. Large normal alleles (Q24-31) were significantly more unstable upon maternal transmissions. In contrast, expanded alleles (Q32-750) were significantly more unstable during paternal transmissions, in correlation with repeat length. Significant correlations were found between the instability and the age at conception in paternal transmissions. In conclusion, intergenerational instability at ATXN2 locus is influenced by the sex, repeat length and age at conception of the transmitting parent. These results have profound implications for genetic counseling services.
['Almaguer-Mederos|L E|LE|0000-0003-0887-2359', 'Mesa|J M L|JML|', 'González-Zaldívar|Y|Y|', 'Almaguer-Gotay|D|D|', 'Cuello-Almarales|D|D|', 'Aguilera-Rodríguez|R|R|', 'Falcón|N S|NS|', 'Gispert|S|S|', 'Auburger|G|G|', 'Velázquez-Pérez|L|L|']
D000328:Adult D000367:Age Factors D000483:Alleles D000067698:Ataxin-2 D005260:Female D018392:Genomic Imprinting D042822:Genomic Instability D006801:Humans D008297:Male D020754:Spinocerebellar Ataxias D018911:Trinucleotide Repeats
intergenerational instability spinocerebellar ataxia type 2 ATXN2 gene CAG/CAA repeat configuration