Though the extent to which common variants in TOMM40 can have APOE-independent effects on disease risk or disease-modifying effects remains uncertain, polymorphisms in TOMM40 have been independently associated with a range of primarily cognition-based neurodegenerative diseases, including AD, frontotemporal dementia and dementia with Lewy bodies, as well as non-pathological ageing8,12–15. Here, APOE is linked to Alzheimer disease.