Among these, mutations in core genes such as Chromosome 9 open-reading frame 72 (C9orf72), TAR DNA-binding protein (TARDBP), fused in sarcoma (FUS), valosin-containing protein (VCP), sequestosome 1 (SQSTM1, also known as p62), ubiquilin 2 (UBQLN2), and coiled-coil-helix-coiled-coil-helix domain containing 10 (CHCHD10), also occur in frontotemporal dementia (FTD), which is the second most common presenile dementia, suggesting that there is a link connecting these two different disorders3. The gene discussed is C9orf72; the disease is frontotemporal dementia.