We all carry several gene variants that do not cause any disease. These are called recessive variants. Most people do not know which genes they have variants in, but as all Cryos donors are screened for a number of genetic diseases, we know that some of our donors are healthy carriers of certain specific genetic variants. These donors can, however, still be a completely safe option for your patients.
On this page, you will find detailed information about the genetics behind using a Known Carrier Donor and how to proceed with this option.
What is a Known Carrier Donor?
A Known Carrier Donor is a donor who is known to be a carrier of one or more specific genetic variants. Everyone has two copies of each gene, and we only need one normal gene to function. Therefore, the donor is a completely normal and healthy individual.
The only way a Known Carrier differs from a standard donor is that we have the information about which genetic variant he or she carries.
Is there a risk associated with using a Known Carrier?
Using donor sperm or eggs from a Known Carrier Donor does not in itself convey a risk to children conceived with his or her donations. Only if both the biological parent and the donor are carriers of a genetic disease-causing variant in the same gene, is there a 25% risk of having a child with that specific condition and a 75 % chance of having a healthy child.
Genetic Matching for enhanced safety
Having a variant in the same gene is very rare. However, at Cryos, the safety and well-being of the children conceived with the help of our donors are our top priority. Therefore, if you or your patient consider choosing a Known Carrier Donor, we recommend that your patients seek genetic counseling in their country to clarify the risk. Depending on the patient’s situation, ethnicity, and family history a genetic test can be a solution to confirm that the patient is not a carrier of a variant in the same gene as the donor.
Your patient can use Cryos' Genetic Matching services or another type of test to undergo a genetic screening. If the test indicates an increased risk of passing on a disease, you can choose a different donor.
Learn more about the genetics behind healthy carriers and Genetic Matching in the video below.
Which genetic variations do we screen for?
Our current genetic carrier test screens for the most common variants, including:
- Cystic Fibrosis
- Hemoglobinopathies (including Alfa thalassemia, Beta thalassemia, and Sickle cell)
- Spinal Muscular Atrophy
- Tay-Sachs
- Non-syndromic deafness (GJB2)
In addition to the above tests, we also screen our egg donors for the following:
- Dystrophinopathies
- Severe hemolytic anemia
- Fragile X
If the genetic test shows that a donor candidate is a carrier of one or more of the recessive conditions mentioned, we will register this in the Summary of Records on the donor’s profile and mark the donor as a Known Carrier.
Why choose a Known Carrier Donor?
Most people do not know which genetic variants they are carriers of. When choosing a Known Carrier Donor, you get the information about one gene variant in the donor. You and your patient then have the chance to take precautions through genetic counseling and possible testing, if needed.
How to use a Known Carrier Donor
Using a Known Carrier Donor follows a similar process to using any other donor, with the added step of seeking genetic counseling and possibly having a genetic test for the genetic parent. Follow the link to read our step-by-step guide on how to order donor sperm or how to order donor eggs.
Cost of using a Known Carrier Donor
The cost of donor sperm or donor eggs from a Known Carrier Donor is the same as a standard donor.
Do you have any questions regarding Known Carrier Donors?
Our Clinic Account Team will be happy to answer any questions you might have related to Known Carrier donors. Please feel free to contact us.