This might not be unexpected given the number of other genes (including VCP, SQSTM1, HNRNPA1, HNRNPA2B1 and MATR3), in which mutations cause clinical syndromes, referred to as multisystem proteinopathies, with ALS, FTD, inclusion body myopathy and bone disease each showing variable penetrance [29]. This evidence concerns the gene HNRNPA2B1 and frontotemporal dementia.