Syndromes caused by chromosomal aneuploidies are widely recognized genetic 
disorders in humans and often lead to spontaneous miscarriage. Preimplantation 
genetic screening is used to detect chromosomal aneuploidies in early embryos. 
Our aim was to derive aneuploid human embryonic stem cell (hESC) lines that may 
serve as models for human syndromes caused by aneuploidies. We have established 
25 hESC lines from blastocysts diagnosed as aneuploid on day 3 of their in vitro 
development. The hESC lines exhibited morphology and expressed markers typical 
of hESCs. They demonstrated long-term proliferation capacity and pluripotent 
differentiation. Karyotype analysis revealed that two-third of the cell lines 
carry a normal euploid karyotype, while one-third remained aneuploid throughout 
the derivation, resulting in eight hESC lines carrying either trisomy 13 (Patau 
syndrome), 16, 17, 21 (Down syndrome), X (Triple X syndrome), or monosomy X 
(Turner syndrome). On the basis of the level of single nucleotide polymorphism 
heterozygosity in the aneuploid chromosomes, we determined whether the 
aneuploidy originated from meiotic or mitotic chromosomal nondisjunction. Gene 
expression profiles of the trisomic cell lines suggested that all three 
chromosomes are actively transcribed. Our analysis allowed us to determine which 
tissues are most affected by the presence of a third copy of either chromosome 
13, 16, 17 or 21 and highlighted the effects of trisomies on embryonic 
development. The results presented here suggest that aneuploid embryos can serve 
as an alternative source for either normal euploid or aneuploid hESC lines, 
which represent an invaluable tool to study developmental aspects of chromosomal 
abnormalities in humans.