The library keeps them for others to use. Similarly, the information in the genes is read, perhaps millions of times in the life of an organism, but the DNA itself is never used up. The genetic information in DNA contains instructions for building molecules that implement all the biological functions of an organism. To make theses molecules from a gene, the information in the DNA is first copied, base for base, into a similar kind of information called RNA . The RNA copy of the gene acts as a messenger to get information from the DNA to the machinery where gene products are made.
Mutations are chemical changes to DNA that produce variations in the genetic code.
Mutations can be inherited from a parent, or may happen during the life of an organism due to environmental influences or other events. Mutations can cause gene products to be built differently, not built at all, or produced in incorrect amounts. This page was developed through the Natural History of Genes, a University of Utah program funded by the Howard Hughes Medical Institute.