Evolutionary dynamics of co-segregating gene clusters associated with complex diseases

Area of Science:

• Genomics
• Evolutionary Biology
• Human Genetics

Background:

• Disease-associated mutations are not randomly distributed in the human genome.
• These mutations often enrich in genomic regions with low recombination rates.
• Genome-wide association studies (GWAS) indicate clustering of single nucleotide polymorphisms (SNPs) linked to complex traits in low-recombination areas.

Purpose of the Study:

• Investigate the accumulation of deleterious mutations in low-recombination regions.
• Examine the role of positive selection and genetic hitchhiking in this phenomenon.
• Understand the evolutionary dynamics shaping disease susceptibility loci.

Main Methods:

• Analysis of publicly available data on complex diseases and population demography.
• Evolutionary analysis of conserved gene clusters.
• Identification of disease-associated SNPs in rearranged genomic regions.

Main Results:

• Observed an enrichment of hitchhiked disease associations in conserved gene clusters under selection.
• Discovered that conserved gene clusters originated from concerted rearrangement events across vertebrate evolution.
• Found distinct clustering of disease-associated SNPs in rearranged, low-recombination, high-gene-density regions (e.g., interleukin cluster on 5q31, RhoA on 3p21) involved in immunity.

Conclusions:

• Multiple lineage-specific rearrangements physically clustered functionally related genes.
• This clustering resulted in an enrichment of susceptibility loci for complex traits.
• Evolutionary dynamics beyond recent adaptations contribute to the formation of linked gene clusters associated with complex diseases.