A mutation is a change in the genetic material (DNA or RNA) of a cell or virus causing a sustained change to some features because of the inherited transmission of the genetic material from generation to generation.
A mutation is an abnormal change in the DNA of a gene, either spontaneously during cell division or in response to external agents known as mutagens. The gene is then altered and passed on to offspring cells. Some mutations have no consequences on the cell. Others are the first stage of a long process of malignant change. Cancer is considered to be a genetic disease as it begins on the gene level within a cell. Cancer, however, is not a true inherited disease.