Rapidly Progressive Frontotemporal Dementia Associated with MAPT Mutation G389R

Area of Science:

• Neurodegenerative Disorders
• Genetics
• Molecular Biology

Background:

• Frontotemporal dementia (FTD) encompasses a broad range of neurodegenerative conditions.
• Genetic mutations, particularly in the MAPT gene, are implicated in some FTD cases.

Observation:

• A 27-year-old patient presented with progressive behavioral disturbances, personality change, and moderate dementia with motor symptoms.
• Magnetic Resonance Imaging (MRI) revealed frontotemporal atrophy.
• The patient experienced rapid progression to severe dementia within three years of symptom onset.

Findings:

• Genetic analysis identified a heterozygous c.1165G>A mutation in the MAPT gene (encoding tau protein), resulting in a glycine to arginine substitution (G389R).
• Structural modeling of the mutant tau protein was performed using I-TASSER software.
• Analysis of MAPT gene transcript and methylation in peripheral blood leukocytes did not reveal mechanisms for incomplete penetrance.

Implications:

• This case highlights an unusual presentation of FTD with early onset and rapid progression associated with a specific MAPT mutation.
• Understanding the structural impact of tau mutations is crucial for FTD research.
• Further investigation into genetic and epigenetic factors may elucidate mechanisms of incomplete penetrance in tauopathies.