Frontotemporal dementia-related gene mutations in clinical dementia patients from a Chinese population

Alzheimer's disease (AD) and frontotemporal dementia (FTD) are two common forms of primary neurodegenerative dementia that show overlapping clinical symptoms. The aim of this study was to perform genetic analyses on GRN, VCP, CHMP2B, FUS, TARDBP, C9orf72 and MAPT genes in Chinese AD and FTD patients. We performed gene sequencing of the GRN, VCP, CHMP2B, FUS, TARDBP, MAPT and C9orf72 genes in 61 clinical AD and 38 FTD Chinese patients. We identified a known mutation of MAPT (p.Pro301Leu, c.902C>T) in four patients from an autosomal dominant FTD family with behavioral variant FTD (bvFTD) and progressive nonfluent aphasia (PNFA) phenotypes, and a novel mutation in MAPT (p.Leu48Val, c.142 G>C) in a sporadic progressive supranuclear palsy patient. Two novel variations in VCP (p.Thr127Ala, c.379A>G; p. Asn401Ser, c. 1202A>G) were present in both a sporadic FTD and an AD case, and a novel deletion in GRN (560del p.Leufs) was found in a sporadic primary progressive aphasia patient. Mutations of VCP, GRN and MAPT genes are present in Chinese FTD cases. In the case of the MAPT mutation, the family presented with both bvFTD and PNFA phenotypes, while the VCP mutation was also related to an early-onset AD phenotype.