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Genes & Disease
How do we get mutations?
Gene mutations can either be inherited from a parent or acquired. A hereditary or germline mutation is present in every cell of the body. They are called germline mutations because they are present in the germ cells or reproductive cells and in this way they can be passed from one generation to the next. These mutations are copied every time a body cell divides.
Acquired mutations or somatic mutations are changes that occur during a persons lifetime. Somatic cells include all body cells except for the reproductive cells. These somatic mutations are changes in the genomic sequence of individual cells and they are only passed to cells that are directly derived from the original cell. These mutations are often a result of the failure of the cells DNA repair mechanism to correct a mistake that has occurred during cell division.
The body's repair machinery is highly accurate most of the time (uncorrected errors occur at the rate of about 1 in every 50 million nucleotides added to the chain) becoming a little less efficient with age. Somatic mutations can also be the result of environmental stresses such as cigarette smoke, over exposure to the sun, radiation, car fumes, pesticides and many more.
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