[Progress of research on induced pluripotent stem cell models for Down syndrome]

With an incidence of 1/800 - 1/600, Down syndrome (DS) is the most common chromosomal disorder in humans. Whilst most DS patients has trisomy 21, a small proportion may carry translocations or mosaicisms involving chromosome 21. The main characteristics of DS include mental retardation, peculiar facies, growth retardation, congenital heart disease, duodenal stenosis, Alzheimer's disease, leukemia, and immunodeficiency, which may be due to increased dosage of critical genes. Recent studies also showed that epigenetic changes may also occur in DS. For research on patients with DS or other trisomies have been restricted by ethical considerations, and commonly used mouse models cannot fully replicate the characteristic features of DS, pluripotent stem cells induced from fetal samples or biopsy tissues from DS patients may generate models with the same genetic content, which may provide idea materials for studying the pathogenesis of DS and customized cell and/or gene therapies.