CHEK2 and breast cancer: Our results are similar to those reporting that there is no association between CHEK2 1100delC (Rashid 2005; Ndawula et al. 2014), I157T (Kilpivaara et al. 2004; Bayram et al. 2012), and del5395bp (Mohelnikova-Duchonova et al. 2010; Cybulski et al. 2007) variations and breast cancer risk and our cases were not selected based on family history.