Art prevents chromosome instability in MSCs. (a) SKY analysis of wild type (WT) (top) or ArtΔ/Δ (bottom) mesenchymal stem cells (MSCs). An example of a chromatid break, typifying damage in ArtΔ/Δ cells, is indicated by an arrow and shown magnified. (b) Summary of spontaneous chromosomal abnormalities in WT versus ArtΔ/Δ. (c) Distribution of chromosome number in WT versus ArtΔ/Δ MSC karyotypes. Shown is the percentage of metaphase spreads from each karyotype harboring the indicated number of chromosomes.