Genetics are incredibly fundamental to your health and personal well-being. Not only do your genetics make you who you are, but they also influence your health and risk for disease.
Everyone has variations in their DNA. While some variations may have little to no effect on a person’s life, there are disease-causing variations that can become a cause for concern. This is where genetic testing comes in.
What is genetic testing?
Clinical genetic testing is a type of medical test done through a healthcare provider used to determine one’s cancer risk. These tests would either look for a one-gene cause of a condition that runs in the family or use multiple genetic markers to estimate the risk of a common but complex health problem. These are not to be confused with DTC kits as genetic tests are administered by healthcare professionals for medical purposes, and not personal use.
How does genetic testing work?
Genetic testing is done by drawing a simple sample from the blood or saliva, which isolates your DNA to decipher the code. Once it has been sent to an accredited laboratory, the sample would be analysed and interpreted by a group of doctors to see if there are any changes or mutations in your DNA that may cause an increased risk for cancer.
While the process may seem rather straightforward and uncomplicated, the part that becomes instrumental and makes a difference is when those results are interpreted and translated into medical recommendations to help patients make the transition. That’s why genetic counselling is essential before proceeding with the testing procedure itself.
What happens after the results are retrieved?
There are three possible result outcomes with every genetic test: positive, negative or inconclusive results.
A positive test result may confirm a variety of outcomes. This includes an indication of a higher risk of developing a chronic disease like cancer, evidence that the person is a carrier of a specific genetic variant, or that a diagnosis has been confirmed.
Since certain family members may have similar genetic material, relatives of the tested patient may want to consider undergoing a genetic test as well.
An important thing to note for individuals undergoing testing is that a positive test result may not necessarily imply that you will get that particular disease. It simply indicates an increased risk of developing that disorder but doesn’t mean it is certain.
For anyone going through genetic testing of any form, the best kind of results are the ones that come out as negative. This indicates that the test didn’t detect a mutated gene, chromosome, or protein in the sample.
Naturally, a negative test result would put anyone’s mind at ease. However, depending on the condition being tested for, the accuracy of the tests may still vary. Since genetic testing may not be able to reveal all the possible defects at once, doctors may suggest additional testing or re-testing at a later date to fully confirm a negative result.
Despite this, patients can be reassured that false-negative results are extremely rare in the case of genetic testing.
On some occasions, an inconclusive or uninformative result may appear. These could occur when natural variations in the DNA do not affect one’s health or when there is insignificant information as to whether the variant is benign or pathogenic.
When the latter happens, further testing may be recommended.
What are the common reasons for genetic testing?
Doctors could order genetic testing for a variety of reasons such as:
- To test for mutations that cause an increased risk for cancer
- To diagnose a particular disease or rare conditions
- To uncover the main cause of the disease
- To determine the various treatment options and plans for the disease
- To come up with a prevention plan that could reduce the risk of getting a certain condition
- To find out if a specific genetic condition runs in your family for early detection
- To find out the chances that a current or potential pregnancy will have the same genetic condition
Common types of tests conducted
1. Diagnostic testing
When an individual experiences several symptoms of a disease that may be caused by mutated genes, diagnostic testing can be used to identify the particular condition causing these genetic changes.
On top of receiving a diagnosis, doctors can also determine the prognosis as well. Common conditions that can be identified with diagnostic testing include down syndrome, Huntington’s disease, or cystic fibrosis.
Unlike regular screening tests that determine an individual’s risk of developing a genetic condition, diagnostic testing goes in-depth and pinpoints the condition itself.
2. Carrier testing
Before starting a family, it is useful to know about the risk of having a child with a genetic disorder based on their family history. That is why some of the most suitable candidates for carrier testing or screening include prospective parents looking to start their own families.
Through a simple blood draw, the results will be able to detect whether you and your partner are gene carriers even if you aren’t displaying any symptoms of the disease.
Some of the most common disorders detected through carrier testing are sickle cell disease, spinal muscular atrophy, and several different cancers.
3. Presymptomatic and predictive testing
Just as its name suggests, presymptomatic or predictive testing is done on asymptomatic individuals who are at risk of contracting a genetic disorder. When there is a family history of a genetic disorder, certain members of the family may want to assess whether they have inherited the disease-causing mutation.
Common diseases that can be identified with presymptomatic or predictive testing include colorectal cancer and Huntington’s disease.
4. Pharmacogenomic testing
Pharmacogenomics looks at the response of a genetic variation that affects the body’s response to specific medicines. The sole purpose of this testing method is to assess treatment efficacy.
Through the DNA sample collected, pharmacogenomic testing helps doctors find the suitable medication and dosage for you as well as if there are any serious side effects from the prescription.
5. Prenatal testing
Unlike carrier testing, prenatal testing is done during pregnancy and used to discern changes or abnormalities in an unborn baby’s genes. This type of testing allows you and your partner to accurately assess whether your child would be born with a birth defect or genetic condition.
Prenatal testing can be conducted using a variety of methods using traditional invasive testing or cell-free DNA testing.
While this form of testing can detect most genetic disorders, it cannot identify all the possible birth defects and inherited disorders and may only be determined after the child has been born.
Get tested with Curie Genetics
The topic of genetics may seem daunting to most families at first, especially since it’s something we cannot change. But here at Curie Genetics, we help you understand your results and what effects they might have on you and your family.
With our team of experienced doctors and genetic counsellors, we will guide you through the testing process from start to finish. From reviewing your family history, ordering the appropriate genetic testing if you wish to proceed, interpreting the results, and everything in between.
Genetic testing can help you take control of your health. By knowing your risk ahead of time, you can make more informed choices with regard to your family’s health and well-being.
Get in touch with us today and we’ll take it from there.