Brief Overview of Genetic Testing & It's Uses

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The human genome is believed to contain around 20,000-25,000 genes. A mutation in any one of these could cause anything from retardation to increasing your chances of cancer. The benefits of genetic testing is that it can find out if an individual is at risk of inheriting any of the diseases that are tested for.

There are many types of genetic testing and more are becoming available. The most well known is prenatal genetic testing to detect changes in a fetus’s genes before birth. This is most commonly done with an amniocentesis, but this process has been known to pose risks, such as miscarriages.

The most widespread use of genetic testing is screening of newborn infants. Millions of babies are tested each year in the U.S. for diseases such as phenylketonuria and congenital hypothyroidism. Other tests are diagnostic and carrier testing to either confirm a diagnosis or let people know if their children are at risk of inheriting a genetic disorder or being a carrier of a condition.

Genetic testing is also used in forensic science and to go back in time to determine ancestry. Unlike the traditional testing to detect gene mutations associated with disease, forensic genetic testing can identify crime victims, rule out suspects or establish biological relationships. Genealogical genetic testing allows one to trace their ancestry. It allows individuals to find out the probability that they are, or are not, related to another person within an estimated number of generations.

Cancer researchers have discovered gene mutations that could increase a woman’s risk of getting cancer. For example those who carry a particular mutation on the BRCA1 gene have an increased risk of breast cancer and genetic testing informs women if they carry this mutation. This kind of genetic testing is called predictive or presymptomatic testing.

Are there Any Risks?

The physical risks associated with most genetic tests are very small. Many of the risks associated with genetic testing involve emotional, financial or social consequences of the test results. Genetic testing is often accompanied by genetic counseling because of the psychological problems that may accompany the results. There are ethical issues that also come up with genetic testing. The possibility of genetic discrimination in employment or insurance is also a concern. People may avoid genetic testing out of fear that it will affect their ability to obtain health or life insurance or find a job. While genetic information is kept confidential there is also US legislation to protect the patient.

Direct to Consumer Genetic Testing

Normally, healthcare professionals such as doctors get patient permission and order the desired test. However, new direct-to-consumer (DTC) genetic testing allows consumers direct access to genetic testing without having to go through the normal channel of a healthcare professional. There are a variety of DTC tests available to the consumer, ranging from testing for breast cancer gene mutations to those mutations linked to cystic fibrosis. Proponents say that by making these tests accessible to consumers it promotes proactive healthcare as well as the privacy of the genetic information. Critics of DTC testing argue that unregulated advertising has allowed companies to exaggerate and convey inaccurate information about the connections between genetic information and the disease risk. For example, just because there is a mutation in a gene it does not necessarily follow that a person will contract the disease associated with the mutation.

Without professional interpretation and guidance, consumers can potentially misinterpret the results causing them to be misdirected about their personal health. There is also a lack of governmental oversight for these DTC genetic tests.