This keyword will open a table of frequencies of the most common types of birth defects in the U. S. population. The overall frequency of these conditions is about one in 25 births. Most of the conditions that have genetic risk factors are complex traits affected by multiple genes; these include disorders of the heart and circulation, muscles and skeleton, genital and urinary tract, and nervous system and eye, which together have an incidence of one in 35.

The debate over the growing and marketing of genetically modified organisms has been fierce, especially in Europe. Opponents call them Frankenstein's plants. They argue that it is foolhardy to plant millions of acres of novel crop plants and let their products enter the food supply without evaluating the possible long-term effects on human health and the environment. Proponents argue that the maintenance of an affordable food supply depends on the increased productivity expected from genetically modified plants. This keyword site provides a balanced discussion of the issues and points out that, while the debate continues, in the United States genetically modified crops already constitute a large portion of the food supply.

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