3. Nucleic sequence and genome analysis

Historically, the first macromolecule sequences obtained were those of proteins. It wasn't until the early 1980s that it became easier to determine the sequence of genes, rather than the sequence of the proteins they code for. There are 3 main reasons for this:

• DNA is a much simpler molecule to extract and purify than proteins, as each protein has a different physico-chemical behavior, while the same protocol can be used for DNA from very different organisms;

• DNA is extremely strong and stable;

• Finally, DNA is made up of 4 types of elementary building blocks, the nucleotides (also known as "nucleotide bases", or simply "bases").

These properties have enabled the automation of DNA sequencing operations and the democratization of the technology...