Explaining drug reactions

Pharmacologist Bob Smith of St Mary's Hospital, London, once took part in one of his own experiments for a medicine to reduce blood pressure. Unfortunately, his body could not break the medicine down properly, so he became very ill for a while. He reacted in this way because he had a particular version of a gene instruction for a protein that helps break down drugs in the body. Individuals with the same version of this gene could potentially be identified before doctors prescribe medicines for them.

DNA analysis of a gene affecting drug metabolism. Each lane shows a different person's DNA: people require different doses depending on the gene variant they have. Nigel Spurr, SmithKline Beecham