Dual multiple change-point model leads to more accurate recombination detection

Motivation: We introduce a dual multiple change-point (MCP) model for recombination detection among aligned nucleotide sequences. The dual MCP model is an extension of the model introduced previously by Suchard and co-workers. In the original single MCP model, one change-point process is used to model spatial phylogenetic variation. Here, we show that using two change-point processes, one for spatial variation of tree topologies and the other for spatial variation of substitution process parameters, increases recombination detection accuracy. Statistical analysis is done in a Bayesian framework using reversible jump Markov chain Monte Carlo sampling to approximate the joint posterior distribution of all model parameters. Results: We use primate mitochondrial DNA data with simulated recombination break-points at specific locations to compare the two models. We also analyze two real HIV sequences to identify recombination break-points using the dual MCP model. Availability: A software program ‘DualBrothers’ implementing the dual MCP model is available in the form of a Java package at http://www.biomath.ucla.edu/msuchard/DualBrothers Contact: msuchard@ucla.edu Supplementary information: http://www.biomath.ucla.edu/msuchard/DualBrothers