Carrier Screening and Family Planning
What is a carrier?
We all get two sets of genes, one from our mother and one from our father. If there is a ‘spelling error’ in a haemoglobin gene passed down from one parent, then the copy from the other parent can function, so the individual has no (or very mild) symptoms.
These people are called carriers, as they do not have the condition, but carry the ‘spelling error’ in one copy of the haemoglobin genes.
If you and your partner are carriers, there is a 25% chance you will have a child with a haemoglobin disorder. There is also a 50% chance your child will be a carrier like you and a 25% chance that your child is completely healthy and is not a carrier themselves.
More than 1 in 20 people worldwide are carriers of a haemoglobin disorder.
Anyone can be a carrier, but there is a greater chance if your family is originally Mediterranean, Middle-eastern, South Asian or Mid to North African.
How do I find out if I’m a carrier?
You can take a simple blood test to determine your carrier status specifically for a haemoglobin disorder.
The blood test is free and can be carried out by your GP.
It is your choice whether you want to be tested or not, now or in the future.
I found out I’m a carrier, now what?
If you are considering having children, your partner may want to be tested too. This will allow you to determine your chance of having an affected child.
This information opens up choices for you and your partner.
This may include:
- discussing a variety of possible reproductive options to reduce the chance of having an affected child
- being able to plan ahead through prenatal testing
- using the information to look out for symptoms in your child and ensure an early diagnosis.
This is something you can discuss with your obstetrician or a genetic counsellor.
You may also wish to tell other members of your family about your carrier status. This is because if you are a carrier, then other members of your family may be carriers too. This could be important so they can make informed choices about future children.
What test do I ask for at the GP?
When going to the GP, ask to be screened for haemoglobinopathy trait.
Specifically, ask for the following tests:
- Full Blood Examination
- Haemoglobin electrophoresis
- Iron studies
After these tests, your doctor might ask you to get additional test for you and/or your partner to further understand your risks and carrier status such as a DNA test.
If your GP is not sure about the tests, ask them to refer to the below protocol for carrier testing in Victoria.
Carrier screening is free for medicare patients.
Know My Trait is an awareness campaign that encourages young people and couples to find out whether they are carriers of a genetic trait that causes Thalassaemia and other blood disorders.
Know My Trait is campaign created by the Thalassaemia and Sickle Cell Society of NSW.
Visit www.knowmytrait.org for information, brochures and other resources!