The Down syndrome (DS), or Trisomy21, is the most frequent aneuploidy in human. The genomic disorder is such an extent that any single cure could overcome all the symptoms (mental retardation, motor defects…). That’s why mouse models’ using allows studies on Hsa21 regions impact in deficits apparition. My PhD project was turned toward the telomeric locus of the Hsa21 framed between Abcg1 and U2af1. We focused our research on two models, Ts1Yah and Ms2Yah, dedicated to this region. The study of those lines, combined with several other transgenic ones, showed the contribution of the interval into the optimisation of motor learning. In a second step, the Cbs gene, candidate on memory loss of function, has highlighted a functional rescue in dose-effect experiment. This discovery paves the way to new therapeutic perspectives.
