Toledo et al. (2013) found that in those with clinical diagnosis of AD or MCI, AD pathology was coincidental in about 40% of subjects with other pathologies such as dementia with Lewy bodies, hippocampal sclerosis, TDP-43 proteinopathy, argyrophilic grain disease and vascular pathology. Similar findings were also reported in independent cohorts (White et al., 2016). The gene discussed is TARDBP; the disease is Lewy body dementia.