This gene is one of several tumor-suppressing subtransferable fragments located in the imprinted gene domain of 11p15.5, an important tumor-suppressor gene region. Alterations in this region have been associated with the Beckwith-Wiedemann syndrome, Wilms tumor, rhabdomyosarcoma, adrenocortical carcinoma, and lung, ovarian, and breast cancer. This gene is imprinted, with preferential expression from the maternal allele. Mutations in this gene have been found in Wilms' tumor and lung cancer. This protein may act as a transporter of organic cations, and have a role in the transport of chloroquine and quinidine-related compounds in kidney. Several alternatively spliced transcript variants encoding different isoforms have been described.