Integrative genetic analysis illuminates ALS heritability and identifies risk genes

Area of Science:

• Neurogenetics
• Molecular Biology
• Cell Biology

Background:

• Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share significant heritability.
• Genetic factors contributing to ALS are increasingly understood, with a focus on RNA-binding proteins and splicing.

Purpose of the Study:

• To investigate the role of splicing variants and RNA-binding proteins in ALS heritability.
• To identify novel genetic loci associated with ALS risk.
• To explore the link between nuclear pore complex defects and ALS pathogenesis.

Main Methods:

• Transcriptome-wide association study (TWAS) to identify ALS-associated loci.
• Analysis of rare variants in candidate genes within a large cohort of ALS/FTD patients.
• Functional studies in patient-derived cells, Drosophila, and zebrafish to assess the impact of NUP50 mutations.

Main Results:

• ALS heritability is enriched in splicing variants and binding sites of key RNA-binding proteins (TDP-43, FUS).
• TWAS identified six ALS-associated loci, including NUP50.
• Rare NUP50 variants are significantly associated with increased ALS risk.
• NUP50 deficiency leads to decreased NUP50 levels, neuronal death, and motor defects in model organisms.

Conclusions:

• Alterations in neuronal splicing are critical in ALS pathogenesis.
• Genetic evidence links defects in nuclear pore components, specifically NUP50, to ALS.
• NUP50 represents a potential therapeutic target for ALS and related neurodegenerative disorders.