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2.10. How to find genes?
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Getting the sequence of the genome is only the beginning, as I explained, once you have the sequence what you want to do is to locate the gene, to predict the function of the gene and maybe study the interaction between genes and proteins. Let's concentrate on the prediction of genes on a genome. How can we find genes using,of course, algorithms? That's what we call genome annotation, the prediction of gene location and the prediction ofthe function of the genes, of the protein coded by the genes. A typical bacterial genome like the E. coli genome is four by five megabases and is the support of 4,500 genes. A human genome is 3. gigabases and is 20,000 genesonly and that was quite a big surprise at the end of human project that biologists expected something like 100,000 genes and the human being has only 20,000 genes. But well, you see it's not somuch different from the number of genes of a bacterium. The factis that the number of proteins is much larger because in eukaryoticorganism, a gene may code for several proteins. So the number of genes is not a good measure here, well whatever. A typical bacterial genome, you have to discover, to predict the location of 4,000 and something genes. How can we proceed? Of course designing an algorithm because you have understood that we cannot do that by hand, so what do we know about gene location?
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2.4. A translation algorithm
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