MAPT and frontotemporal dementia: There are also transgenic linesof laboratory animals carrying genetic variants that causehereditary frontotemporal dementia (Dawson et al., 2007).However, these model systems have some limitations due todifferences in the signs of ageing between mice and humansand even differences between mouse and human tau protein (Iovino et al., 2015; Hernández et al., 2020).