Figure 4

Freezing-induced DSBs. (a) Single DNA image after freeze/thawing to −25 °C (upper: slow frozen) and −80 °C (lower: quick frozen). (b) Average lengths of DNA, 〈L〉, vs. the concentration of DMSO. (c) The number of DSBs per 10 kbp, 〈n _f 〉, vs. the concentration of DMSO.