Recent literature has shown that CBS can be caused by four distinct pathologies: corticobasal degeneration (CBS-CBD), progressive supranuclear palsy (CBS-PSP), Alzheimer’s disease (CBS-AD) and frontotemporal lobar degeneration (FTLD) with ubiquitin-only immunoreactive inclusions, which show immunoreactivity to the TAR DNA-binding protein (CBS-TAR). The gene discussed is RBM8A; the disease is Alzheimer disease.