Source:http://linkedlifedata.com/resource/umls/id/C1704939
NCI: Human ABCB1 wild-type allele is located in the vicinity of 7q21.1 and is approximately 210 kb in length. This allele, which encodes multidrug resistance protein 1, is involved in transmembrane transport. Amplification of the ABCB1 gene is a major determinant in the development of multi-drug resistance, which decreases the effectiveness of many chemotherapeutic agents used in cancer treatment.