In particular, the genes ABCA2, ABCA3, ABCB1, ABCB4, ABCC1, ABCC2, ABCC4, ABCC5, ABCC10, ABCC11, ABCG1, and ABCG2 are directly related to tumour chemoresistance [24,28]. The gene discussed is ABCB4; the disease is neoplasm.