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Genetic testing

Carrier screening

Nine out of ten children born with CF are born into families with no known family history of the condition. In families with no family history, both parents of the child who is born with CF must be carriers of the gene change that causes CF.

An estimated 1 in 25 Australians carry the gene changes that can cause CF, and most people are unaware if they are a carrier. CF carrier screening services are available to help you and your partner find out whether you are among the one million Australians who carry the CF gene change.

If both parents are carriers of the CF gene change, then with each pregnancy there is a 25% chance of that child having CF. Being a carrier of the CF gene change does not mean you have CF and carriers usually display no symptoms of CF.

What is CF carrier screening (testing)?

CF carrier screening is a genetic test that will help to identify if you have changes to the CF gene.

The test involves providing a blood or saliva sample and requires a referral from your GP, obstetrician, geneticist, or gynaecologist. There are around 2,000 gene changes that cause CF, and a typical CF screening will identify the most common CF gene changes in Australia. However, there is still a small risk that you may be a carrier of a rare CF gene change.

If you have a family history of CF, it is important to tell your GP, obstetrician or gynaecologist before providing your sample for screening. This will ensure that you are being tested for the most common CF gene changes as well as the specific gene change relevant to your family.

On November 1, 2023, reproductive carrier testing for cystic fibrosis, fragile X syndrome and spinal muscular atrophy was made available for every eligible Australian, thanks to two new Medicare item numbers, allowing people to make more informed choices regarding family planning. 

The test can be ordered prior to pregnancy or early in a pregnancy.

For more information on genetic testing:

Could you be a carrier?

Making the decision to know your CF carrier status through genetic testing is a choice only you can make. Knowing whether you are a carrier can help inform you of your reproductive options.

You can discuss your CF carrier screening options with your GP, obstetrician or a genetic counsellor.

Genetic counsellors are accredited health professionals who can talk about your family history, explain your test options, and discuss what your test results mean to help you and your family make informed decisions.

Is it better to know my CF carrier status?

Everyone’s reason for wanting or not wanting to know their CF carrier status will be different. What is important is that you feel you have made an informed choice that suits your particular situation and needs.

However, the more open people are about the existence of CF in the family and the availability of testing like CF carrier screening, the more informed people can be when they make their own choices about finding out their CF carrier status when they are ready.

CFCC individuals having an opportunity to make informed life and reproductive choices as a result of CF carrier screening.

Some parents are interested in finding out the carrier status of their children who do not have CF. The Human Genetics Society of Australasia guidelines on genetic counselling recommend that minors should only have carrier testing when the results will inform their health management in the immediate future.

It is important to note that newborn screening (heel prick test) and CF carrier screening are different. Newborn screening will generally not identify a child’s CF carrier status.

If you decide to be tested

Visit your healthcare provider – Let your healthcare provider (such as your GP or obstetrician) know that you wish to have genetic carrier screening. Your healthcare provider will need to complete a referral organise this testing.

Take the test – A blood or saliva sample is collected and sent to a laboratory for genetic testing. 

Visit your healthcare provider to get your results – Typically your results will be communicated to your healthcare provider within 2-4 weeks. They will inform you if you carry a CF gene change.

If the test shows you are a carrier – We recommend that you discuss your result with a genetic counsellor. Depending on your result, your healthcare provider or a genetic counsellor will discuss carrier testing for your partner if they have not already had a test. If the results show that both you and your partner are carriers of CF, a genetic counsellor can help you to consider your options.

Carrier screening resources