However, rarer forms of FTLD and/or ALS have been associated with mutations in valosin‐containing protein (VCP) 8, CHMP2B9, ubiquilin 1(UBQLN1) 10, optineurin (OPTN) 11 and sequestosome 1 (SQSTM1) (also known as p62) 12 genes. Here, OPTN is linked to amyotrophic lateral sclerosis.