Inheritance of Frontotemporal Dementia

Abstract

FRONTOTEMPORAL dementia (FTD) is a group of degenerative disorders that overlap in their clinical and neuropathological findings. At least 25 kindreds have demonstrated heritable FTD disorders.¹ Each disorder was named after its distinguishing characteristic (eg, pallido-ponto-nigral degeneration, familial multiple system tauopathy, familial progressive subcortical gliosis, hereditary dysphasic disinhibition dementia, and disinhibition-dementia-parkinsonism-amyotrophy complex [DDPAC]).^1-3 Yet, as a group, these disorders share many clinical and neuropathological findings. Clinical features common throughout the sporadic and inherited FTD range of disorders are presenile onset; behavioral, extrapyramidal, and cognitive (especially frontal executive dysfunction) symptoms; and hypoperfusion in the frontotemporal region seen on single photon emission computed tomographic (SPECT) scans. However, there is a wide range of presentations that includes depression, bipolar disorder, and alcoholism.^2,4 Early personality changes and psychiatric disorders often precede frank dementia by many years. Neuropathological findings shared by all FTD disorders are nonspecific and include atrophy in frontotemporal regions, neuronal loss, neuropil vacuolization of superficial cortical layers, and gliosis in gray and white matter.¹