Carrier testing is done to see if you are a carrier of an autosomal recessive or X-linked condition. A carrier is a person who has 1 copy of a pathogenic variant in a gene but does not typically show symptoms of the genetic condition themselves. Being a carrier means that you can pass the pathogenic variant down to your children.

Some carriers can experience milder or different symptoms and are called “manifesting carrier” or an “affected female.” For example, this can happen with Fragile X syndrome and with Duchenne muscular dystrophy.

Carrier testing may be offered to people who have a family history of a genetic condition and to their partners. It is meant to identify couples at risk of having a child with a serious genetic condition and to support reproductive planning. Carrier testing is sometimes called preconception testing.

Carrier testing is generally only offered to adults 18 years of age and older, as the results do not impact health in children.

X-linked carrier testing is only needed for people assigned female sex at birth. For those assigned male sex at birth, they will either have the condition or will not be a carrier, and so do not need X-linked carrier testing.

Carrier testing may also be offered to some couples based on specific ethnic backgrounds. For example:

• Cystic fibrosis is more common in people who have family origins from the Quebec regions of Saguenay Lac-St-Jean and Charlevoix.
• Tay-Sachs disease is more common in people with Ashkenazi Jewish heritage.
• Inherited anemias, like sickle cell disease, occur more often in people with African, Asian, or Mediterranean backgrounds. However, screening for inherited anemias often begins with a complete blood count (CBC) before genetic testing.

A diagnosis of a genetic condition can be made by specific health or development concerns, by the results of a genetic test, or by both. A diagnosis that is based only on the presence of specific health or development concerns is called a clinical diagnosis.

Diagnostic testing is done to identify the specific pathogenic variant that is causing a condition for people with a clinical diagnosis. It may also be done when there is a strong suspicion of a genetic condition based on symptoms. A positive genetic test would help to confirm the diagnosis.

Sometimes, a genetic diagnosis of a condition can lead to specific treatments or recommendations for your medical care. However, a genetic diagnosis may not change medical care.

Identifying a pathogenic variant with genetic testing will tell us how the genetic condition is inherited, which can be helpful for reproductive planning or in offering genetic testing to other family members.

If a diagnostic genetic test is negative, the next steps will depend on several factors, like what genetic condition is suspected and the type of genetic test that was done. Learn more about a negative genetic test result when you have a genetic condition.

Babies born in Alberta are tested for certain treatable conditions after birth.

Newborn blood spot screening is provided through the Alberta Newborn Screening Program within Primary Care Alberta. The program helps your baby have the best start in life. Early screening for certain conditions makes sure your baby gets treatment when it can help the most.

Predictive testing (sometimes called presymptomatic testing) is done for a healthy adult family member of a person with a genetic condition. More rarely, healthy children with a sibling or parent with a genetic condition may have predictive testing if a positive result would immediately change their medical care. If a positive result would not immediately change the medical care of a healthy child, then genetic testing would not be done until adulthood (age 18 or older). For example, if a parent has hereditary breast and ovarian cancer due to a pathogenic variant in the BRCA1 gene, genetic testing is not offered to their children until age 18 because early screening for breast cancer does not begin until age 20 to 25.

Predictive testing happens through a type of test called familial variant testing, which looks to see if you have the same pathogenic variant that was found in a family member.

To have predictive testing done, your family member with a genetic condition must have had genetic testing done first and had a positive result. Learn more about genetic testing when your family member has a genetic condition.

Predictive testing for certain genetic neurodegenerative conditions

There are special protocols for predictive testing for genetic neurodegenerative conditions associated with dementia or changes in cognition. These are conditions caused by damage to the nervous system over time, especially in the brain. Examples of these genetic neurodegenerative conditions include Huntington’s disease, early-onset familial Alzheimer's disease, and familial ALS (amyotrophic lateral sclerosis).

Predictive testing for genetic neurodegenerative conditions associated with dementia or changes in cognition in Alberta follows international guidelines on genetic counselling and testing for neurodegenerative conditions. The process for predictive testing may vary a bit between sites in Alberta, but typically involves genetic and psychosocial counselling, a neurological exam, and a blood test. It can take 6 weeks to 6 months to complete the predictive testing process.

Pre-implantation genetic testing is done in combination with in vitro fertilization (IVF). It is used to screen embryos for a known genetic condition or chromosome differences. Only embryos that do not have the genetic condition or a chromosome difference are used for a pregnancy.

This testing is not currently covered by the Alberta Health Care Insurance Plan. It is typically arranged through a fertility clinic because it is done with IVF.

Prenatal testing is done during a pregnancy to check for genetic conditions that can be identified before birth. Prenatal testing may be done to:

• screen a pregnancy to see if there is a higher-than-average chance that the pregnancy has a genetic condition
• diagnose a genetic condition in a pregnancy where a health concern has been identified on a test like an ultrasound
• test a pregnancy for a genetic condition that is known to be in the family

The results of prenatal testing can be used to guide medical care, both before and after birth. In some cases, you may use the results to guide decisions about whether or not to continue the pregnancy. They may also be used for future reproductive planning.

Learn more about the types of prenatal tests that are available.​​​