A Novel ITM2B Mutation Associated with Familial Chinese Dementia.

Mutations in ITM2B have been found to be associated with familial Danish dementia (FDD) and familial British dementia (FBD). Here, we describe a patient with dementia caused by a novel ITM2B p.*267Leuext*11 mutation. The patient presented with dementia, ataxia, deafness, and paraplegia. Amyloid PET and Tau PET showed abnormal deposition of amyloid and tau protein in brain. Summarized from previous 26 FBD and FDD cases, the clinical phenotype of ITM2B; p.*267Leuext*11 mutation in ITM2B is different from the features of FBD and FDD. Our findings increased genetic knowledge of familial dementia and extend the ethnic distribution of ITM2B mutations.