Progress of research on induced pluripotent stem cell models for Down syndrome / 中华医学遗传学杂志

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.

Application of Karyomapping for the prenatal diagnosis of five families affected with facioscapulohumerial muscular dystrophy type 1 / 中华医学遗传学杂志

OBJECTIVE@#To assess the value of Karyomapping for the prenatal diagnosis of facioscapulohumerial muscular dystrophy type 1 (FSHD1).@*METHODS@#Peripheral blood and chorionic villi samples were collected from five families affected with FSHD1. Linkage-based diagnosis was carried out by using the Karyomapping method. Diagnosis for two fetal samples was carried out with the next-generation optical mapping system.@*RESULTS@#The results of Karyomapping showed that three fetuses inherited the risky 4q35 region of the proband and two fetuses did not. The fetuses of families 1 and 2 received further diagnosis by the next-generation optical mapping system, and the results were consistent with those of Karyomapping.@*CONCLUSION@#Karyomapping has enabled prenatal diagnosis for the five families affected with FSHD1. The method was faster and simpler compared with conventional strategies, though its feasibility still needs further validation. Since there were no SNP loci designed on the Karyomap chip for the DUX4 gene and its 3' flanking regions, misjudgment due to chromosomal recombination could not be completely eliminated. The accuracy of this method still needs further validation.