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2.8. DNA sequencing
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During the last session, I explained several times how it was important to increase the efficiency of sequences processing algorithm because sequences arevery long and there are large volumes of sequences, so it's now the time to ask: but where these sequences come from? This is the process of sequencing. DNA sequencing is a physical operation through which a DNA molecule is read, that is every nucleotide along the strand of the molecule is read and then a text is producedas a succession of the nucleotides as letters. So from the DNA molecule tothe text through what is a sequencer. Sequencers are smaller and smaller and smaller and they may now be placed onto a desk for example, they are so small they can be placed onto a desk.
Indeed sequencing is one of the so-called exponent cell technology, why exponential technology? It's because in the last few years, the efficiency in terms of speed of the sequencesincreased exponentially, the cost of sequences decreased exponentially. You have to remember that the first DNA sequences were obtained in the early 70s and there was a technological break through less than ten years ago with theso-called next generation sequences and this is really somethingwhich is important because now we are able to sequence quickly and cheaply.
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