Selective Sweeps Under Dominance and Inbreeding

Area of Science:

• Evolutionary Genetics
• Population Genetics
• Molecular Evolution

Background:

• Identifying loci under positive selection is a key goal in evolutionary genetics.
• Selective sweeps, including hard and soft sweeps, are patterns indicating positive selection.
• Current theories often overlook the effects of dominance and inbreeding on sweep dynamics.

Purpose of the Study:

• To investigate the influence of arbitrary dominance and self-fertilization on hard and soft selective sweep signatures.
• To understand how these factors affect the detectability and characteristics of selective sweeps.
• To propose methods for differentiating between hard and soft sweep scenarios.

Main Methods:

• Theoretical modeling of selective sweep patterns.
• Analysis of genetic data under varying degrees of self-fertilization and dominance.
• Comparison of sweep signatures in outcrossing versus self-fertilizing populations.

Main Results:

• Increased self-fertilization maintains sweep signatures over longer genetic distances.
• Self-fertilization leads to faster fixation of beneficial alleles.
• Dominance can influence sweep patterns, particularly in outcrossing populations, depending on the origin of the beneficial variant.

Conclusions:

• Self-fertilization and dominance significantly alter the patterns of selective sweeps.
• Distinguishing between hard and soft sweeps is challenging due to these factors.
• The study provides insights and proposes methods to better differentiate sweep scenarios in empirical data.