Mutations: Changing the Code

A mutagen is any agent (physical, chemical or biological) capable of altering the structure of DNA within our cells. This program explores how some mutations are a natural process resulting from errors in the copying and repair of DNA and how some mutagens naturally exist in the world around us (UV radiation, cosmic rays and some radioactive isotopes). Others are specific chemicals that have been synthesized for use in manufacturing or other industries. Mutagens may also arise during the metabolism of certain foods. In general mutagens act either directly on the DNA themselves or produce chemicals that then act directly on the DNA to cause substitutions, deletions, insertions, or rearrangements of the important genetic code. If DNA alterations occur in germline (egg or sperm) cells the altered DNA may become the basis for an inherited disease. In many cases mutagens may also lead to the development of cancers.