Fig. 1

Established amniocyte lines and their hybridization signals. a Primary amniocytes were transfected with SV40LT and positive clones were obtained after selection with G418 (inverted microscope; × 40). b Monolayer adherent spindle-shaped amniocyte lines were formed when cultured in DMEM containing 10% fetal bovine serum (inverted microscope; × 40). c Comparison of quality-control cells and primary amniocytes. a and b show hybridization signals of trisomy 13 and 21 in quality-control cells, respectively. c and d show the signals of trisomy 18 and XXY in quality-control cells, respectively. The number of sky blue, green, and red signals represent the number of chromosomes 18, X, and Y, respectively. e and f show the signals of the 13/21 two-color probe and 18/X/Y trichrome probe in primary cells, respectively