Linda Crnic Institute for Down Syndrome, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
Genes (Basel). 2021 Oct 26;12(11):1697. doi: 10.3390/genes12111697.
Down syndrome (DS), trisomy of human chromosome 21 (Hsa21), is the most common genetic cause of intellectual disability. The Dp10(1)Yey (Dp10) is a mouse model of DS that is trisomic for orthologs of 25% of the Hsa21 protein-coding genes, the entirety of the Hsa21 syntenic region on mouse chromosome 10. Trisomic genes include several involved in brain development and function, two that modify and regulate the activities of sex hormones, and two that produce sex-specific phenotypes as null mutants. These last four are the only Hsa21 genes with known sexually dimorphic properties. Relatively little is known about the potential contributions to the DS phenotype of segmental trisomy of Mmu10 orthologs. Here, we have tested separate cohorts of female and male Dp10 mice, at 3 and 9 months of age, in an open field elevated zero maze, rotarod, and balance beam, plus the learning and memory tasks, spontaneous alternation, puzzle box, double-H maze, context fear conditioning, and acoustic startle/prepulse inhibition, that depend upon the function of the prefrontal cortex, striatum, hippocampus, and cerebellum. We show that there are age and sex-specific differences in strengths and weaknesses, suggesting that genes within the telomere proximal region of Hsa21 influence the DS phenotype.
唐氏综合征（DS）是人类 21 号染色体（Hsa21）三体，是智力障碍最常见的遗传原因。Dp10(1)Yey（Dp10）是一种 DS 的小鼠模型，它在 25%的 Hsa21 蛋白编码基因上为三体，在小鼠 10 号染色体上具有 Hsa21 的全部同线区。三体基因包括几个参与大脑发育和功能的基因，两个调节和调节性激素活性的基因，以及两个产生作为缺失突变体的性别特异性表型的基因。后四个是唯一具有已知性别二态性特性的 Hsa21 基因。关于 Mmu10 同源物的片段三体对 DS 表型的潜在贡献相对知之甚少。在这里，我们在开阔场高架零迷宫、转棒和平衡木以及学习和记忆任务、自发交替、拼图盒、双 H 迷宫、上下文恐惧条件反射和听觉惊跳/前脉冲抑制中测试了 3 个月和 9 个月龄的雌性和雄性 Dp10 小鼠的独立队列，这些任务依赖于前额叶皮层、纹状体、海马体和小脑的功能。我们表明，在强度和弱点方面存在年龄和性别特异性差异，这表明 Hsa21 端粒近端区域内的基因影响 DS 表型。
