Atxn3^tm1.2Hlp

This allele is derived from Atxn3tm1Hlp. An expanded CAG trinucleotide repeat, (CAG)2(CAAAAG)(CAG)82 which encodes 85 glutamines interrupted by a lysine at the fourth residue [Q(3)KQ(82)], was inserted into exon 10. An FRT flanked PGK-neo cassette was removed via flp-mediated recombination. PCR confirmed insertion of the expansion and Western blot analysis confirmed protein expression in the brain, heart, liver, muscle and spleen. CAG repeat length sizing in offspring of heterozygotes shows a modest tendency toward CAG repeat contraction upon maternal transmission of the mutant allele and stabilization or mild expansion upon paternal transmission. Atxn3tm1Hlp also contains a tandem duplicate of the targeting vector, which contains a 3' part of intron 9, the CAG repeat expansion-containing exon 10 and a 5' part of intron 10. The duplicate was removed through subsequent flp-mediated recombination. This leaves an allele with one copy of the expanded repeat-containing exon 10 and, in intron 9, one loxP and one FRT site. (J:244808)