I started my masters in September of 2008. I am currently working with Next Generation Sequencing data and working on several features of SHRiMP. I will include more updates about my main recent research project in early 2009 :).
As I described above, I also developed the FRESCO sequence aligner with Michael Brudno in 2006/7, and worked on Sea Level Theory with Jerry Mitrovica in 2007/8. The FRESCO aligner (PubMed ID 18229672) introduces the class of Rectangular Scoring Schemes for pairwise alignment, and allows for alignment under any scoring function from this wide class under polynomial time. The running time is improved with several heuristics.
(abstract)
While the popular DNA sequence alignment tools incorporate powerful heuristics to allow for fast and accurate alignment of DNA, most of them still optimize the classical Needleman Wunsch scoring scheme. The development of novel scoring schemes is often hampered by the difficulty of finding an optimizing algorithm for each non-trivial scheme. In this paper we define the broad class of rectangle scoring schemes, and describe an algorithm and tool that can align two sequences with an arbitrary rectangle scoring scheme in polynomial time. Rectangle scoring schemes encompass some of the popular alignment scoring metrics currently in use, as well as many other functions. We investigate a novel scoring function based on minimizing the expected number of random diagonals observed with the given scores and show that it rivals the LAGAN and Clustal-W aligners, without using any biological or evolutionary parameters. The FRESCO program, freely available at http://compbio.cs.toronto.edu/fresco, gives bioinformatics researchers the ability to quickly compare the performance of other complex scoring formulas without having to implement new algorithms to optimize them.
In sea level theory, we redefined several concepts in the theory of Sea-Level variation, and introduced sediment movement in our theory.I implemented a sea-level algorithm, with similarity to that of Kendall et. al. (2005), that includes the new definitions and sediment addition. The results are currently being evaluated and the relevant publication is to be submitted soon.
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