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5.6. The diversity of bioinformatics algorithms
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Descriptif
In this course, we have seen a very little set of bioinformatic algorithms. There exist numerous various algorithms in bioinformatics which deal with a large span of classes of problems. For example, read assembly. We have seen how NGS sequencers produce large sets of reads, small sequences which overlap. And the problem of assembly isto use the overlap in order to ordering this read and reconstructing the whole genomic sequence. This is the overlapping and you see that you can use this overlap to get a longer sequence. Of course, here the example issimple: you have to imagine a set of millions of reads to beassembled into genomic sequences of millions or billions of bases. A second class of problems issequence mapping and comparison. We have seen sequence comparison. What about sequence mapping? You remember this situation in which biologists get what they call "cDNA". Experimentally, this is a sequence of DNA and they want to map this sequence of DNA on the sequence of the genome in order to say: well, this is an exon, this i an exon and so on.
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5.4. The UPGMA algorithm
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5.2. The tree, an abstract object
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5.5. Differences are not always what they look like
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5.3. Building an array of distances
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5.7. The application domains in microbiology
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5.1. The tree of life
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Avec les mêmes intervenants et intervenantes
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1.1. The cell, atom of the living world
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1.9. Predicting the origin of DNA replication?
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2.8. DNA sequencing
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4.6. A path is optimal if all its sub-paths are optimal
RechenmannFrançoisA sequence alignment between two sequences is a path in a grid. So that, an optimal sequence alignmentis an optimal path in the same grid. We'll see now that a property of this optimal path provides
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5.1. The tree of life
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1.4. What is an algorithm?
RechenmannFrançoisWe have seen that a genomic textcan be indeed a very long sequence of characters. And to interpret this sequence of characters, we will need to use computers. Using computers means writing program.
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2.10. How to find genes?
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3.8. Probabilistic methods
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4.3. Measuring sequence similarity
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5.3. Building an array of distances
RechenmannFrançoisSo using the sequences of homologous gene between several species, our aim is to reconstruct phylogenetic tree of the corresponding species. For this, we have to comparesequences and compute distances
