Mouse models of frontotemporal dementia: A comparison of phenotypes with clinical symptomatology

- Frontotemporal dementia is the second most common form of young onset dementia.
- There is much clinical, pathological and genetic heterogeneity within FTD.
- Mouse models focusing predominantly on recapitulating neuropathological and molecular changes of disease have been developed, expressing a single specific protein or genetic mutation.
- Together with the species-typical presentation of functional deficits, this makes generalized conclusions drawn from these models that are directly translatable to humans difficult.
- Understanding the phenotypical presentations in mice and how they may relate to clinical symptomology in humans is essential for advancing translation in FTD.

Frontotemporal dementia (FTD) is the second most common cause of young onset dementia. It is increasingly recognized that there is a clinical continuum between FTD and amyotrophic lateral sclerosis (ALS). At a clinical, pathological and genetic level there is much heterogeneity in FTD, meaning that our understanding of this condition, pathophysiology and development of treatments has been limited. A number of mouse models focusing predominantly on recapitulating neuropathological and molecular changes of disease have been developed, with most transgenic lines expressing a single specific protein or genetic mutation. Together with the species-typical presentation of functional deficits, this makes the direct translation of results from these models to humans difficult. However, understanding the phenotypical presentations in mice and how they relate to clinical symptomology in humans is essential for advancing translation. Here we review current mouse models in FTD and compare their phenotype to the clinical presentation in patients.