Figure 3.

FA NSPCs display chromosomic aberrations. (A) γ-H2AX foci were numerous in the VZ of fancg^−/− embryos, but infrequent in fancg^+/+ controls. Cytogenetic analyses were performed on embryonic NSPCs in culture. Figures of abnormal metaphases are shown to illustrate the most frequent aberrations that were observed in fanca^−/− NSPC cultures; (B) the arrow points a chromatid break; (C) a complex rearrangement is surrounded (C′); and an endoreplication is shown (arrowheads pointed out a pair of chromosomes) (D). (E) Quantifications were performed on 300 metaphases obtained from four embryos at the first and second passage in culture, and they showed increased levels of chromatid breaks and rearrangements (radial formation, endoreplication) in fanca^−/− compared with fanca^+/+ controls. ^**P<0.01; ^***P<0.005.