Reeves R H, Irving N G, Moran T H, Wohn A, Kitt C, Sisodia S S, Schmidt C, Bronson R T, Davisson M T
Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Nat Genet. 1995 Oct;11(2):177-84. doi: 10.1038/ng1095-177.
Trisomy 21 or Down syndrome (DS) is the most frequent genetic cause of mental retardation, affecting one in 800 live born human beings. Mice with segmental trisomy 16 (Ts65Dn mice) are at dosage imbalance for genes corresponding to those on human chromosome 21q21-22.3--which includes the so-called DS 'critical region'. They do not show early-onset of Alzheimer disease pathology; however, Ts65Dn mice do demonstrate impaired performance in a complex learning task requiring the integration of visual and spatial information. The reproducibility of this phenotype among Ts65Dn mice indicates that dosage imbalance for a gene or genes in this region contributes to this impairment. The corresponding dosage imbalance for the human homologues of these genes may contribute to cognitive deficits in DS.
21三体综合征或唐氏综合征（DS）是智力发育迟缓最常见的遗传病因，在每800个活产婴儿中就有1例受其影响。具有16号染色体节段性三体的小鼠（Ts65Dn小鼠），其与人类21号染色体21q21-22.3区域（包括所谓的唐氏综合征“关键区域”）上的基因存在剂量失衡。它们不会出现早发性阿尔茨海默病病理特征；然而，Ts65Dn小鼠在一项需要整合视觉和空间信息的复杂学习任务中确实表现出行为受损。这种表型在Ts65Dn小鼠中的可重复性表明，该区域一个或多个基因的剂量失衡导致了这种损伤。这些基因的人类同源基因相应的剂量失衡可能导致唐氏综合征患者的认知缺陷。
