How far from the SNP may the causative genes be?

Area of Science:

• Genetics
• Genomics
• Bioinformatics

Background:

• Genome-Wide Association Studies (GWAS) identify numerous disease-associated single nucleotide polymorphisms (SNPs).
• A significant challenge lies in mapping these SNPs, particularly those in non-coding regions, to the specific genes they affect, hindering mechanistic insights.
• Current SNP-to-gene mapping methods often fail to implicate many SNPs and reveal limited phenotype-pathway associations.

Purpose of the Study:

• To develop and validate a pathway-based approach for improved SNP-to-gene mapping.
• To investigate the distance between associated SNPs and implicated genes.
• To identify potential mechanisms underlying SNP-gene associations, especially for distant gene interactions.

Main Methods:

• Utilized a pathway-based approach to map SNPs to genes.
• Analyzed the physical distance between SNPs and their associated genes.
• Investigated genetic variations, such as insertions/deletions, near SNPs linked to distant genes.

Main Results:

• Affected genes can be located up to 2 megabase pairs (Mbps) away from the associated SNP, not necessarily the closest genes.
• The proposed pathway-based approach enables mapping of nearly all SNPs to genes.
• This method revealed 435 significant phenotype-pathway associations, a substantial increase from existing methods.
• SNPs mapped to distant genes showed a higher frequency of large insertions/deletions nearby.

Conclusions:

• A pathway-based approach significantly enhances SNP-to-gene mapping accuracy and scope.
• This method substantially increases the number of identified phenotype-pathway associations, aiding disease mechanism discovery.
• Large insertions/deletions may play a role in mediating the effects of SNPs on distant genes.