Progranulin genetic variability contributes to amyotrophic lateral sclerosis

Area of Science:

• Neurogenetics
• Molecular Neurology
• Genomic Medicine

Background:

• Progranulin (PGRN) gene mutations are linked to frontotemporal dementia (FTD).
• Amyotrophic lateral sclerosis (ALS) shares clinical and pathological features with FTD.
• Investigating PGRN's role in ALS is crucial due to disease overlap.

Purpose of the Study:

• To investigate the genetic variability of the PGRN gene in patients with ALS.
• To determine the association of PGRN variants with ALS risk, age of onset, and survival.

Main Methods:

• Sequencing of all PGRN exons, boundaries, and regulatory regions in Belgian ALS patients.
• Genotyping of common PGRN polymorphisms in Belgian and Dutch patient and control cohorts.
• Association studies to evaluate the impact of PGRN variants on ALS clinical parameters.

Main Results:

• Eleven PGRN mutations were identified in ALS patients, with five affecting protein sequence or levels.
• Common PGRN variants and haplotypes were significantly associated with earlier onset of ALS.
• These variants correlated with reduced survival duration in both Belgian and Dutch ALS cohorts.

Conclusions:

• PGRN functions as a disease modifier in amyotrophic lateral sclerosis.
• PGRN genetic variability influences the course of ALS, leading to earlier onset and shorter survival.
• Findings underscore the importance of PGRN in neurodegenerative disease pathways.