Genetic Testing

Genetic testing involves examining a person's DNA in order to find changes or mutations that might put an individual, or that individual's children, at risk for a genetic disorder. These changes might be at the chromosomal level, involving extra, missing, or rearranged chromosome material. Or the changes might be extremely small, affecting just one or more of the chemical bases that make up the DNA. In a broader sense, genetic testing includes other types of testing that provide information about a person's genetic makeup, such as enzyme testing to diagnose or identify carriers for a genetic condition such as Tay-Sachs disease.

With hundreds of genetic tests available, determining who should be offered testing and under what circumstances testing should occur is relatively complicated. In general, testing is offered to those at highest risk based on their ethnic background, family history, or symptoms. However, just because genetic testing is possible and a person is at risk, this does not mean it should be offered or will be useful to that person. Genetic testing is unlike other medical tests in that individual results may also provide information about relatives, may be able to predict the likelihood of a future illness for which treatment may or may not be available, may put the person at risk for harm such as discrimination, or may have limited accuracy. There are a number of settings in which genetic testing occurs and within each setting there are a variety of indications and considerations for testing.