ERCC4 and Cowden syndrome 1: Nonetheless, as mentioned before, some mutations in genes XPB,XPD, XPF, XPG, orERCC1, which participate in NER (Menck and Munford, 2014), may result in a combined phenotypeof CS and XP (Lehmann 1982, 2014; Weedaet al., 1990; Moriel-Carretero et al., 2015).