Notice
1.6. GC and AT contents of DNA sequence
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Descriptif
We have designed our first algorithmfor counting nucleotides. Remember, what we have writtenin pseudo code is first declaration of variables. We have several integer variables that are variables which cantake as a value an integer. One, two, three minus five and so on. We have the sequence of characters we want to interpret, declare as a character string oflengths and define. Then we have the initializationof our different variables. This symbol is a symbol for assignment, it means that zero becomes the value of total nb, nbT and soon and so on and here we say: index takes the value one. It means that we position at the beginning of the sequence and what we do is that we repeat allthese blocks of operation for the first position, the second position, the third and so on, so on, until the end of the sequence. And for each position we take the current corrector, here, A for example and we look if itis an A, a C, a G, a T and we increment, we increase by one,the corresponding counter. OK, at the same time we increasethe total number of characters by one and we add one to theindex so that we come from this position to this position.
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Welcome to this introduction to bioinformatics. We will speak of genomes and algorithms. More specifically, we will see how genetic information can be analysed by algorithms. In these five weeks to
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1.10. Overlapping sliding window
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We have made some drawings along a genomic sequence. And we have seen that although the algorithm is quite simple, even if some points of the algorithmare bit trickier than the others, we were able to
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1.4. What is an algorithm?
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1.8. Compressing the DNA walk
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1.2. At the heart of the cell: the DNA macromolecule
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During the last session, we saw how at the heart of the cell there's DNA in the nucleus, sometimes of cells, or directly in the cytoplasm of the bacteria. The DNA is what we call a macromolecule, that
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1.5. Counting nucleotides
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In this session, don't panic. We will design our first algorithm. This algorithm is forcounting nucleotides. The idea here is that as an input,you have a sequence of nucleotides, of bases, of letters,
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1.9. Predicting the origin of DNA replication?
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Avec les mêmes intervenants et intervenantes
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1.9. Predicting the origin of DNA replication?
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We have seen a nice algorithm to draw, let's say, a DNA sequence. We will see that first, we have to correct a little bit this algorithm. And then we will see how such as imple algorithm can provide
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2.8. DNA sequencing
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3.5. Making the predictions more reliable
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4.6. A path is optimal if all its sub-paths are optimal
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5.1. The tree of life
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1.3. DNA codes for genetic information
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2.2. Genes: from Mendel to molecular biology
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2.10. How to find genes?
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3.8. Probabilistic methods
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