Today we have the ability to gather more information about ourselves than ever before. Progress in genetic research and genetic testing has led to new discoveries and a greater understanding of genetic conditions. Genetic testing is becoming more convenient and financially accessible. However, while genetic data may be easily obtainable, experts in the field recommend seeking professional assistance in the comprehension and application of results.
Susan Hassed, Ph.D., is a licensed certified genetic counselor. She is also the director of the Masters of Science in Genetic Counseling program and a clinical associate professor in the Department of Pediatrics, Section of Genetics, at the University of Oklahoma Health Sciences Center (OUHSC) in Oklahoma City.
As a genetic counselor, Hassed helps individuals and families through the process of examining and understanding the impact of genetic testing. It’s a journey that can include helping identify the genetic component of an individual’s disease to assist in treatment as well as determining a person’s risk of developing an inherited medical condition.
“My work is a mixture of cool science, psychology and caring,” says Hassed. “Genes are the recipes in our bodies that make us who we are. We all have genes that aren’t working correctly, but if we’re not experiencing problems, we don’t usually care.”
Hassed explains that there is a broad range of genetic diseases that manifest in various ways – genetically, physically and psychologically. While some infants have a problem at birth, other disorders may not develop until adulthood.
[pullquote]“There are many ethical, legal and psychological issues related to genetic testing,” she says. “Positive and negative results can be empowering. Management of risk takes commitment from both the physician and the patient.”[/pullquote]
“For instance, in a child with a disorder, if we can find the underlying cause, it can help us provide a prognosis. We can assist parents in preparing for expected challenges, make goals for accomplishments and provide an idea of what their future might look like,” says Hassed.
She adds that families also use genetic testing when discussing family planning. Couples may want to discover their chances of passing along an inherited condition or want to understand the chance of a second child having a disorder their sibling was born with.
Lori Carpenter, a licensed genetic counselor for Saint Francis Genetics in Tulsa, shares an example of how genetic testing can be very beneficial to patients, in helping to decide on a specific medical treatment.
“Breast and ovarian cancer syndrome [can be] caused by genetic changes in one of two genes, BRCA1 or BRCA2,” says Carpenter. “If a variant is identified in one of those genes, these individuals have a significantly higher risk of developing breast and ovarian cancer. There are specific, recommended surgical options to help these women dramatically reduce their risk of developing those cancers by 80 to 90 percent.”
Carpenter says that for other individuals born with a collection of medical problems (cleft lip, structural heart defect or spina bifida, for example), genetic testing may be the only way to diagnose the underlying cause.
“Having a genetic diagnosis may help to guide medical management and offer opportunities to participate in research studies, but often times it is most beneficial in providing families with a diagnosis and some guidance on future expectations,” says Carpenter.
Dr. Lara Theobald, a medical oncologist at INTEGRIS Cancer Institute in Oklahoma City, explains that genetic testing in oncology is primarily used for predictive purposes – helping to identify patients and families at high risk for developing cancer and, on occasion, helping to guide treatment decisions.
“The benefit in testing unaffected individuals rests in guiding management of risk, such as increased screening tests, prophylactic surgeries or medications,” says Theobald. “Determining whether a patient is in an increased risk group for breast cancer can be helpful in optimizing strategies for screening and clinical management. The limitation is that testing doesn’t necessarily accurately predict an individual’s risk for developing cancer over a specified time frame. Penetrance, environmental factors, exposure…all may play a role in an individual’s susceptibility to developing a cancer.”
While genetic testing provides a wealth of information, Hassed says it’s important to understand that even if you are considered “high risk” for a specific condition, it doesn’t provide a guarantee that you will develop it.
“Among a population with an 85 percent chance of getting breast cancer due to an inherited predisposition, 15 percent will never develop it for an unknown reason,” says Hassed. “Good nutrition and normal care still count in predicting your health and genes continue to change. We have to do the best we can with what we have and use the information we have to our benefit.”
Carpenter encourages individuals or families interested in genetic counseling or testing to talk to their physician, who can refer them to a genetic counselor.
“Genetic counselors are specially trained to help patients make informed, personalized decisions about their genetic health,” says Carpenter. “Genetic counselors also have the knowledge to identify reputable labs to conduct testing and help the patients and the providers understand the genetic results; seeking genetic counseling prior to and after genetic testing is always recommended.”
When speaking with patients about the use of genetic testing, Theobald tries to always be upfront about the issues involved.
“There are many ethical, legal and psychological issues related to genetic testing,” she says. “Positive and negative results can be empowering. Management of risk takes commitment from both the physician and the patient.”
Genetic testing detects changes in an individual’s chromosomes, genes or protein. The tests usually include studying the deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) extracted from a person’s blood or other body fluids such as saliva or tissue. Genetic testing assists in diagnosing a suspected genetic condition and helps individuals discover their chances of developing or passing on a genetic disorder.
According the National Human Genome Research Institute, there are typically three types of genetic tests.
• Gene tests (individual genes or relatively short lengths of DNA or RNA are tested)
• Chromosomal tests (whole chromosomes or very long lengths of DNA are tested)
• Biochemical tests (protein levels or enzyme activities are tested)