AICDA and cancer: Returning to the cancer analogy and the link with deaminase action, as with the triggering of Ig SHM itself (reviewed in Di Noia and Neuberger, 2007, Teng and Papavasiliou, 2007, and again in Steele, 2009, Maul and Gearhart, 2010, and Steele, 2016), we and others have analysed and interpreted cancer data which suggest that DNA C-to-U deamination at off-target (i.e. non-Ig) genomic sites by AID/APOBEC deaminases triggers the recruitment of an ‘Ig SHM-like’ response (Lindley, 2013; Lindley and Steele, 2013).