RNF20 and cystic fibrosis: Consistent with prior work (Yuen et al., 2007), deletion of BRE1 or LGE1 resulted in significant CF loss rates (0.78% and 0.85%, respectively) (Figure 1A), which were 5.7- and 6.3-fold higher than that in wildtype cells (0.13%), suggesting a role for Bre1–Lge1 in accurate chromosome segregation.