Molecular biology is a scientific discipline at the crossroads between genetics and biochemistry. It is increasingly used in medical diagnosis, where it enables the identification of infectious agents by the direct identification of the gene specific to that agent. It can also be used to detect genetic diseases or cancer by identifying the abnormal gene. Amplification techniques have over the last decade allowed for molecular biology to become a more accessible, automated and routine diagnostic tool.
PCR (polymerase chain reaction) allows a single DNA sequence to be replicated millions of times. Real-time PCR (qPCR) enables the quantitative measure of DNA and ARN molecules and therefore the quantification of the level of infection linked to a given pathogenic agent.