OPTN and motor neuron disorder: In recent years, mutations in a number of different genes have been implicated as causative for ALS or motor neuron disease, including the genes encoding AR (androgen receptor), TDP-43 (TAR DNA binding protein), FUS (a component of a fusion protein in malignant liposarcoma), OPTN (optineurin), ANG (angiogenin), ALS2 (alsin – a G-protein exchange factor), FIG4 (FIG4 homolog - phosphatase), SETX (senetaxin – RNA helicase), UBQLN2 (ubiqulin 2 – ubiquitin binding protein), and VCP (Valosin-containing protein) {http://alsod.iop.kcl.ac.uk/default.aspx}.