GENETIC EVIDENCE FOR A PLEISTOCENE POPULATION EXPLOSION.

Area of Science:

• Population genetics
• Evolutionary biology
• Bioinformatics

Background:

• Mitochondrial DNA (mtDNA) mismatch distributions provide insights into population size history.
• Sudden changes in population size leave detectable signatures in genetic data.
• Previous methods for analyzing population history have limitations.

Purpose of the Study:

• To develop statistical methods for estimating population size changes from mtDNA mismatch distributions.
• To infer past population dynamics, specifically focusing on human population expansion.
• To provide confidence regions for parameter estimates.

Main Methods:

• Modeling sudden population size changes (growth or shrinkage).
• Developing statistical estimators for population parameters (θ₀, θ₁, τ).
• Applying methods to published human mitochondrial DNA data.

Main Results:

• The developed statistical methods are well-behaved and robust to simplifying assumptions.
• Estimates for population parameters (θ₀, θ₁, τ) can be reliably obtained.
• Analysis of late Pleistocene human mtDNA data suggests a significant population expansion.

Conclusions:

• The statistical framework effectively reconstructs population size history from mtDNA data.
• A major human population expansion occurred in the late Pleistocene, as inferred from mitochondrial DNA.
• This approach offers a valuable tool for studying evolutionary history in various species.