C3orf23 (chromosome 3 open reading frame 23), also known as FLJ41686, MGC119530, MGC119531, MGC119532, MGC119533 or DKFZp313N062, is a 496 amino acid protein that exists as four alternatively spliced isoforms. C3orf23 is encoded by a gene mapping to human chromosome 3p21.33. Chromosome 3 is made up of approximately 214 million bases encoding over 1,100 genes. Notably, there is a chemokine receptor gene cluster and a variety of human cancer related loci on chromosome 3. Particular regions of the chromosome 3 short arm are deleted in many types of cancer cells. Key tumor suppressing genes on chromosome 3 encode apoptosis mediator RASSF1, cell migration regulator HYAL1 and angiogenesis suppressor SEMA3B. Marfan Syndrome, porphyria, von Hippel-Lindau syndrome, osteogenesis imperfecta and Charcot-Marie-Tooth disease are a few of the numerous genetic diseases associated with chromosome 3.