What is a gene?
(Lansing State Journal, May 31, 1995)


Every living organism is made up of cells.  Every cell contains DNA.  DNA is a long molecule that encodes all the information an organism needs to survive.

For the most part, this information consists of the different kinds of proteins an organism needs to produce in order to function.  For instance, a bacteria cell needs to produce certain specific proteins to survive.  Some proteins are used for chemical reactions, some are used to make more complex proteins and some are used for structural purposes.  The information about which proteins need to be produced is encoded in the bacteria's DNA.

A gene is a section of DNA that codes for a specific protein.  One gene codes for only one protein.

The types of genes an organism has determine the characteristics of that organism.  Sometimes one gene can determine a particular characteristic.  For instance, the height of a pea plant is determined by one gene.  Other times, a number of genes are required to express a particular characteristic.  Eye color in humans, for example, is determined by several different genes.

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