GMNN and neoplasm: Geminin identifies the proportion of tumour cells traversing through S-G2-M phase, and therefore the gemininLI to Ki67LI ratio (geminin/Ki67) provides a measure of the relative length of G1 in dynamic cell populations, with higher geminin/Ki67 ratios corresponding to a shortening in the length of G1 phase (Eward et al, 2004; Wharton et al, 2004; Shetty et al, 2005).