Mutations are inherited from a parent and are present throughout a person’s life in virtually every cell in the body. Also called germ-line mutations because they are present in the parent’s egg or sperm cells. Mutations occur at some time during a person’s life and are present only in certain cells but not in every cell in the body. The changes can be caused by environmental factors such as ultraviolet radiation from the sun or can occur if an error is made as DNA copies itself during cell division.
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