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Heuristics for the inversion median problem
Vaibhav Rajan1, Andrew Wei Xu, Yu Lin
1Laboratory for Computational Biology and Bioinformatics, EPFL, CH-1015 Lausanne, Switzerland. vaibhav.rajan@epfl.ch
BMC Bioinformatics
|February 4, 2010
Summary
A new heuristic, ASM, significantly improves the inversion median problem for comparative genomics. This method provides near-optimal solutions quickly, resolving a major computational bottleneck in whole-genome studies.
Area of Science:
- Genomics
- Phylogenetics
- Computational Biology
Background:
- Genome rearrangements are crucial for phylogenetics and comparative genomics.
- The median problem, finding a median genome from three given genomes, is fundamental.
- Existing heuristics for the inversion median problem, like MGR, have limitations.
Purpose of the Study:
- To develop a unifying framework for median heuristics.
- To introduce a novel, highly efficient heuristic for the inversion median problem.
- To address the computational bottleneck in whole-genome comparative studies.
Main Methods:
- Developed a unifying framework to analyze and order existing median heuristics.
- Introduced a new heuristic (ASM) that leverages input data throughout computation.
- Conducted extensive experiments to compare ASM with existing methods.
Main Results:
- The new heuristic, ASM, demonstrates superior accuracy and significantly faster running times compared to existing methods.
- ASM typically yields solutions within 1% of optimal.
- ASM efficiently handles large genomes (25,000 genes) in seconds to minutes, unlike MGR which can take days for smaller datasets.
Conclusions:
- ASM effectively resolves the computational challenges associated with finding inversion medians.
- The new heuristic provides near-optimal solutions rapidly, even for the largest genomes.
- This advancement facilitates more efficient whole-genome comparative studies.
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