ODF3B, also known as ODF3L3 (outer dense fiber protein 3-like protein 3), is a 253 amino acid protein belonging to the ODF3 family. Existing as two isoforms produced by alternative splicing, ODF3B contains one DUF1309 repeat. The gene that encodes ODF3B maps to human chromosome 22, which contains over 500 genes and about 49 million bases. Being the second smallest human chromosome, 22 contains a surprising variety of interesting genes. Phelan-McDermid syndrome, Neurofibromatosis type 2 and autism are associated with chromosome 22. A schizophrenia susceptibility locus has been identified on chromosome 22 and studies show that 22q11 deletion symptoms include a high incidence of schizophrenia. 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 leukemia.