Importantly, all FTD associated with LMNA-myopathy were caused by hypertrophy of type 2 fibers as compared with age-matched controls, whereas CFTD with mutations in ACTA1 or TPM3 showed selective type 1 fiber atrophy but no type 2 fiber hypertrophy.
Our report further supports this association and suggests inclusion of molecular testing for LMNA in the differential diagnosis of myopathies with FTD due to the risk for life threatening events.