The lethally irradiated recipients were injected with single HSCs sorted from Aldh2−/−Fancd2−/− and control mice on a C57BL/6Jo1a × 129S4S6/Sv F1 background (CD45.2, 8-to-12 weeks old). Bone marrow cells from these mice were extracted with IMDM medium (GIBCO), filtered through a 70-μm strainer, spun down for 5 min at 1,200 r.p.m. and resuspended in 6 ml IMDM medium at room temperature. These cells were then overlaid onto 6 ml Lympholyte M (Cederlane) in a 15-ml Falcon tube and spun down for 20 min at 1,400g at room temperature with the brake off. The interface containing the mononucleated cells was transferred into another 15-ml tube and topped up with ice-cold MACS buffer (PBS pH 7.2, 0.5% BSA, 2 mM EDTA). After 5 min of centrifugation at 1,200 r.p.m., the cell pellets were resuspended in 320 μl of MACS buffer, stained with the lineage-depletion kit (130-090-858, MACS Miltenyi Biotec) following the manufacturer’s instructions and passed through LS magnetic columns. Lineage-depleted cells were spun down for 5 min at 1,200 r.p.m. and the pellets were resuspended in 200 μl MACS buffer with the
