TNRC6B is a 1,723 amino acid protein that exists as two alternatively spliced isoforms and is thought to be involved in mRNA cleavage events. Expressed ubiquitously, TNRC6B contains one glycine tryptophan (GW)-rich N-terminal domain, one central glutamine-rich region and one C-terminal RNA recognition motif and is encoded by a gene that maps to human chromosome 22. Mutations in several of the genes that map to chromosome 22 are involved in the development of Phelan-McDermid syndrome, Neurofibromatosis type 2, autism and schizophrenia. Additionally, translocations between chromosomes 9 and 22 may lead to the formation of the Philadelphia Chromosome and the subsequent production of the novel fusion protein BCR-Abl, a potent cell proliferation activator found in several types of leukemias.