Related Experiment Video
Updated: Aug 12, 2025
Abbiategrasso Brain Bank Protocol for Collecting, Processing and Characterizing Aging Brains
Published on: June 3, 2020
Clinical features and biomarkers of semantic variant primary progressive aphasia with MAPT mutation
Jing Xu1, Yanmin Xia1,2, Meng Meng3
1Department of Neurology, Tianjin Neurological Institute, Tianjin Medical University General Hospital, 154 Anshan Road, Heing District, Tianjin, 300052, China.
Background:
Semantic variant primary progressive aphasia (svPPA) is generally sporadic, with very few reports of tau pathology caused by MAPT mutations.
Methods:
A 64-year-old man was diagnosed with svPPA with MAPT P301L mutation. Clinical information, cognitive and language functions, multimodal magnetic resonance imaging (MRI), blood biomarkers, fluorodeoxyglucose (FDG) imaging and tau positron emission tomography (PET) were obtained.
Results:
Semantic memory impairment was the earliest and most prominent symptom in this family. Tau accumulation and hypometabolism were observed prior to brain atrophy in mutation carriers. Plasma NfL and GFAP concentrations were elevated in the two svPPA patients. Some relative decreases and some relative increases in regional cerebral blood flow (CBF) as measured by arterial spin labelling (ASL) were observed in mutation carriers compared to noncarriers.
Conclusions:
This study describes a large svPPA-affected family with the MAPT P301L mutation and provides an ideal model for inferring underlying pathology and pathophysiological processes in svPPA caused by tauopathies.
Insights
This study identifies a family with semantic variant primary progressive aphasia (svPPA) caused by a MAPT P301L mutation. Early semantic memory impairment and tau pathology precede atrophy in mutation carriers.
Area of Science:
- Neuroscience
- Genetics
- Neurology
Background:
- Semantic variant primary progressive aphasia (svPPA) is typically sporadic.
- MAPT mutations are rarely reported causes of tau pathology in svPPA.
Purpose of the Study:
- To investigate a family with svPPA linked to the MAPT P301L mutation.
- To characterize the clinical, imaging, and biomarker profile of svPPA due to tauopathy.
Main Methods:
- Clinical assessment and cognitive/language function evaluation.
- Multimodal neuroimaging including MRI, FDG-PET, and tau-PET.
- Analysis of plasma biomarkers (NfL, GFAP) and regional cerebral blood flow (ASL).
Main Results:
- Semantic memory impairment was the earliest and most prominent symptom.
- Tau accumulation and hypometabolism preceded brain atrophy in mutation carriers.
- Elevated plasma NfL and GFAP, with altered regional CBF, were observed in patients.
Conclusions:
- This family with MAPT P301L mutation serves as a model for tauopathy-driven svPPA.
- Provides insights into the pathophysiology of svPPA and potential therapeutic targets.
Related Concept Videos
01:26Alzheimer's Disease: Overview
The clinical diagnosis of AD hinges on the presence of memory and other cognitive impairments. Biomarkers, such as changes in Aβ...
01:15Parkinson's Disease: Overview