About Genetic Testing
Genetic testing is a specialized form of medical testing that identifies mutations in genes, changes in chromosomes or altered levels of proteins.
When physicians suspect a patient has a genetic condition, they may refer the patient for a genetic consultation. At that consultation, genetic
testing may be discussed and performed. Genetic testing can help confirm or rule out the presence of a genetic disease or determine the chance
of that patient passing down a hereditary disorder to future children. The Greenwood Genetic Center applies cutting-edge technology to perform
over 200 individual diagnostic tests in our laboratories.
These tests fall under three main categories: biochemical, cytogenetics and molecular.
Genetic testing can offer benefits for patients regardless of the test outcome. Many of our patients express their sense of relief when a negative
result frees them from worry and unnecessary medical screening. Positive results, too, can decrease the level of stress that comes with uncertainty.
Confirming a diagnosis empowers the patient to begin a path of disease prevention and/or preparation for future treatment options.
Our genetic testing includes:
- Prenatal testing detects changes in the chromosomes or genes of a baby before birth. This type of testing is offered if there
is an increased risk of a disorder for the baby.
- Newborn screening follow-up testing identifies genetic disorders that benefit from early treatment.
- Diagnostic testing can be done at any time during a person’s life, sometimes even before birth. Diagnostic testing identifies
chromosomal conditions and specific genetic conditions to find answers and guide treatment.
- Predictive testing, also known as pre-symptomatic testing, detects gene mutations to determine if a person is at risk to develop
certain disorders before symptoms arise
- Carrier Testing can identify if an individual is a carrier for a genetic disorder that could be passed on to their children.
Types of Genetic Testing
Our laboratory staff and faculty strive to provide exceptional service. We provide rapid and accurate diagnoses, helping patients better understand
the cause, treatment and management of a disorder if one is diagnosed. Understanding the focus of each testing lab may help patients and their
families feel more at ease with the process of genetic testing.
- Biochemical Lab - The Greenwood Genetic Center’s biochemical lab provides screening and diagnostic tests for inherited metabolic
disorders including lysosomal storage diseases, mucolipidoses, congenital disorders of glycosylation, and inborn errors of metabolism.
The lab also provides follow-up testing to confirm results from the SC Newborn Screening Program and monitors patients on various treatments.
- Cytogenetics Lab - Finding abnormalities of the number or structure of chromosomes, as well as diagnosing and guiding treatment
for hematological malignancies is the focus of our cytogenetics lab. Analyses include chromosome studies, or karyotypes, microarray testing,
and FISH analysis.
- Molecular Lab - The molecular diagnostic laboratory analyzes DNA for genetic disorders. In this lab we test for a variety
of genetic disorders, many of which are rare. GGC maintains a special interest in conditions related to X-linked intellectual disability,
autism and birth defects, but offers testing for a wide array of conditions Prenatal testing is also available in certain situations.
Why Genetic Testing
Genetic testing is complicated. There are lots of things to consider when deciding whether or not genetic testing is indicated or right for you
or your family. The Greenwood Genetic Center's genetic professionals are prepared to help explain what tests, if any, are indicated based upon
your personal and family medical history and physical exam. We will discuss the risks, benefits and limitations of genetic testing, and genetic
testing is only performed with the full consent of the patient or their parents.
Genetic testing may be offered if:
- You or your child have features or symptoms that may be caused by a genetic disorder. You may have even been searching for an answer for months
or years. These symptoms may include developmental delay, learning difficulties, a birth defect, growth problems, multiple medical issues,
or unusual characteristics. Genetic testing may be able to confirm a diagnosis, ending the uncertainty and providing information on how
to best manage your condition.
- You are well, but have a family history of a genetic condition. Genetic testing can help predict if you are likely to be affected by the condition
in the family and if it may be passed on to your children.
- You are pregnant or planning a pregnancy and there is a reason to suspect a genetic disorder could be present in the baby, such as unusual
ultrasound findings or a family history of a genetic condition.
Most genetic testing is performed by a blood sample, either through a blood draw from your arm or a finger stick. Some tests require other sample
types, such as urine.
Some prenatal testing is done through invasive testing such as amniocentesis or chorionic villus sampling. If this is indicated, your physician
or genetic counselor will discuss the risks, benefits, and limitations in greater detail.