The β-globin gene cluster resides in the chromosome region 11p15.5, harboring important immunity genes and IGF2, H19, PHLDA2/TSSC3, TRIM3, and SLC22A18 genes associated with cancers and gliomas.
SLC22A18, solute carrier family 22, member 18, has been proposed to function as a tumor suppressor based on its chromosomal location at 11p15.5, mutations and aberrant splicing in several types of cancer and down-regulation in glioblastoma.
Our laboratory has found genomic imprinting of a large genomic domain of human 11p15.5, identifying six imprinted genes within this domain: (a) insulin-like growth factor II (IGF-II), an important autocrine growth factor in a wide variety of malignancies; (b) H19, an untranslated RNA that is a putative growth suppressor gene regulating IGF-II; (c) p57KIP2, a cyclin-dependent kinase inhibitor that causes G1-S arrest; (d) KvLQT1, a voltage-gated potassium channel; (e) TSSC3, a gene that is homologous to mouse TDAG51, which is implicated in Fas-mediated apoptosis; and (f) TSSC5, a putative transmembrane protein-encoding gene.