Additionally, Dunford et al. have proposed the biallelic expression of six specific X-chromosome ‘escape from X-inactivation tumour suppressor’ [97] genes (e.g., ATRX, CNKSR2, DDX3X, KDM5C, KDM6A, and MAGEC3) in females as a protective factor against X-inactivation loss of function mutations [97]. This evidence concerns the gene DDX3X and neoplasm.