Sex-specific DNA methylation differences in Amyotrophic lateral sclerosis

Area of Science:

• Genetics and Epigenetics
• Neuroscience
• Human Disease Research

Background:

• Sex is a critical factor influencing disease incidence, progression, and outcomes.
• Amyotrophic Lateral Sclerosis (ALS) exhibits a higher incidence in males, suggesting a role for sex-based biological differences.

Purpose of the Study:

• To conduct a large-scale, blood-based epigenome-wide association study meta-analysis to identify sex-associated DNA methylation patterns in ALS.
• To characterize the genomic locations and regulatory potential of these sex-associated differentially methylated positions (saDMPs).
• To investigate the association between identified saDMPs and overall survival in ALS patients.

Main Methods:

• Performed an epigenome-wide association study meta-analysis on DNA methylation data from 9274 individuals (5529 males, 3975 females).
• Utilized stringent quality control measures for data analysis.
• Applied Cox proportional hazards models to assess the relationship between DNA methylation and ALS survival.

Main Results:

• Identified 226 ALS-specific sex-associated differentially methylated positions (saDMPs) linked to 159 unique genes.
• Found ALS saDMPs are enriched at enhancers and 3'UTRs, and associated with transcription factors like ESR1 and REST.
• Discovered two saDMPs (cg14380013, cg06729676) significantly associated with ALS patient survival.
• Identified 10 additional genes potentially regulated by ALS saDMPs through chromatin loop interactions.

Conclusions:

• This study provides a comprehensive catalogue of sex-associated DNA methylation sites in ALS.
• The findings elucidate the characteristics and potential regulatory roles of these saDMPs in ALS.
• This resource is valuable for future research into the influence of sex on ALS incidence, progression, and risk.