(b) FACS profile of the percentage of WT and Samhd1 KO CH12F3-2A cells undergoing IgA switching following transfection with the indicated plasmids. The number in the FACS plot represents the percentage of cells expressing IgA on their surface. (c) Summary of the FACS data obtained from two independent experiments. The data are shown as percentage of IgA expressing cells upon CSR induced by blunt (left) or staggered (right) DSBs (n = 2; mean + sd; two-tailed unpaired Student's t-test); ns = not significant. 