We also find evidence of known disease‐associated gene deletions in our cohorts, such as a common 30kb deletion of APOBEC3B (chr22:38982347‐38992804) that has been associated with increased risk of lung cancer, prostate cancer, (Gansmo et al., 2018), breast cancer, (Han et al., 2016; Long et al., 2013; Xuan et al., 2013) and HIV‐1 susceptibility (Singh et al., 2016), as well as a common CNV at the FCGR3B locus (1:161623196‐161631963) linked to autoimmune disease susceptibility (Fanciulli et al., 2007) and malaria severity (Faik et al., 2017). This evidence concerns the gene APOBEC3B and breast cancer.