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Genetic Testing: What to Consider When Ordering a Genetic Test

The term "genetic testing" covers an array of techniques including analysis of human DNA, RNA or protein. Genetic tests are used as a health care tool to detect gene variants associated with a specific disease or condition, as well as for non-clinical uses such as paternity testing and forensics.

In the clinical setting, genetic tests can be performed to confirm a suspected diagnosis, to predict the possibility of future illness, to detect the presence of a carrier state in unaffected individuals (whose children may be at risk), and to predict response to therapy. They are also performed to screen fetuses, newborns or embryos used in in vitro fertilization for genetic defects.

Scientists are revealing ever more associations between particular gene mutations and disease, and over a thousand tests can now determine whether a person carries a particular disease-associated allele. As the number of tests continues to increase, their use in the health care setting is becoming more commonplace. The resources provided in this section give an overview of what to consider when ordering a genetic test.

Pharmocogenomics and Pharmacogenomic Testing

Pharmacogenetic Testing is a new type of genetic testing. This type of test examines a person's genes to look at how drugs would move through the body and be broken down. The goal of pharmacogenetic testing is to have drug treatments that are specific to each person. For example, a test used in patients who have chronic myelogenous leukemia can show which patients would benefit from a medicine called Gleevec. Another test looks at a liver enzyme called cytochrome P450, which breaks down certain types of drugs.

Gene alterations can affect how well people's bodies break down certain drugs. People with a less active form of the enzyme might get too much of a drug. Pharmacogenetic testing can help make sure that people get the right amount of a medicine.

Uses of Genetic Testing

Where can I find more information about genetic tests?

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Last updated: November 13, 2013