CHANCE AND PROBABILITY IN BIOINFORMATICS

The discussion regarding the conceptions of chance and necessity has often been at the centre of attention for scientists. The greater emphasis ascribed to the role of chance in the life sciences, as opposed to physics, can be explained by the fact that the hilosophical, ideological and, above all, religious implications of biology and biochemistry have always been very important. Chance takes on a scientific value when it becomes possible to deal with it according to the laws of probability. But before using these laws, we need to understand the precise interpretation to be attributed to the concept of probability, in order that we can give it, at very least, an operative definition. In the field of molecular biology, to take a particular example, the shift from the concept of chance to the concept of probability has been realized by means of the definition of the informational metaphor. This has allowed us to perceive the living organism as being composed of a set of symbols, analysable through the use of frequentist statistics. In reality, this metaphor, although it has allowed us to obtain many important scientific results, does not allow us to solve all the problems presented. Specifically, it does not enable us to understand, in an exhaustive manner, the role of chance in scientific research; and some important questions remain unresolved, such as the relationship between microscopic and macroscopic levels, the attribution of meanings to genetic codes, and the control of complexity