When making a baby, how important is Carrier screening?

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Igenomix is a world leader in reproductive genetics, with laboratories in over 20 countries. With a global team of specialists working together to make a world in which infertility is no longer an impossible barrier to overcome.

Our UK team have collaborated with IVF clinics and patients across the country to provide testing to support fertility treatment and preparations to expand families. We are excited to partner with My Surrogacy Journey to offer genetic testing to IPs and support alternative routes to pregnancy. Having worked with Michael and Wes on several projects, we are incredibly proud to partner for this fantastic initiative.

Igenomix and MSJ

Together with the MSJ team, we have integrated part of our reproductive genetic testing portfolio into the MSJ pathway. Providing IP’s with key information as they plan their journey.

This is centred on two main tests:

• CGT Plus – carrier screening
• NACE/NIPT – non-invasive prenatal screening

What is carrier screening?

Genetic diseases are caused by genetic alterations (also called ‘mutations’) – these are changes to our genes. Alterations associated with recessive genetic disease can be present in DNA without affecting the individual. They are a carrier of the condition. Most people carry at least one genetic condition without knowing it.

Carrier screening is a test to look for specific genetic alterations in an individual’s genes. Being a carrier means that you carry a dormant genetic alteration in you. This could be passed on to your children in the future. If two individuals who carry genetic alterations for the same condition – called ‘co-carriage’ – provide the gametes (sperm and egg) to have a child, there is a risk that the child will be affected by this genetic condition. Many of these conditions are lethal or severely life-limiting so with this knowledge carriers can consider their reproductive choices armed with better information.

What is CGT Plus?

CGT Plus is a carrier screening test, ideally performed before conceiving, using either a blood or saliva sample. CGT Plus analyses hundreds of genes to determine whether an individual is a carrier of any of the genetic conditions included in the test.

When both people who provide the gametes (e.g., an IP and an egg donor) are screened using CGT Plus, we can provide a combined result to tell you whether you are a high-risk match (you both carry mutations in the same gene), or low-risk (we haven’t detected any co-carriage).

Using CGT Plus massively decreases the risk of having a child with serious conditions such as Cystic Fibrosis, Tay-Sachs Disease, and Spinal Muscular Atrophy

Before having CGT Plus testing, we will offer you a counselling session with our genetic counsellor to discuss the test and any specific family history information or concerns you may have.

What is aneuploidy in a foetus?

Sometimes, there are problems with the amount of DNA present in the cells of a developing foetus. For example, there may be too many or too few copies of specific chromosomes. This includes:

• Trisomy – where there is an extra copy of a specific chromosome
• Monosomy – where there is a missing copy of a specific chromosome
• Partial/segmental abnormalities – where there are large changes in the amount of genetic material, but not whole extra or missing copies of chromosomes.

One well known example of aneuploidy is Down’s syndrome, which occurs when a foetus or individual has an extra copy of chromosome 21 (trisomy 21).

What is NACE?

NACE is a type of non-invasive prenatal screening test that is performed during pregnancy using a blood sample from the surrogate carrying the pregnancy. NACE can detect DNA from the foetus in the blood, and analysis of this DNA allows us to detect certain aneuploidies in the foetus. NACE poses no risk to your baby.

Working with My Surrogacy Journey, we are providing our most advanced version of the test – NACE 24.

William Evans from Igenomix

NACE 24 looks at all chromosomes, where most non-invasive prenatal tests only look at a limited number of chromosomes. This means that there are a wider number of conditions that NACE 24 can detect. Some of these – such as Down’s syndrome, Turner syndrome, and Edwards’ syndrome – can lead to the birth of a child with a genetic condition. Most of these conditions will sadly end with miscarriage or stillbirth.

NACE 24 provides you with important information about your pregnancy, and we will offer you genetic counselling if you have a positive NACE result to help you understand what this means and what your next steps might be.

Your journey

By including CGT Plus in your surrogacy journey, you significantly reduce the chance of having a child with an inherited condition like cystic fibrosis, while NACE 24 ensures that you have important information about your pregnancy.

We hope that these tests, with support from the MSJ team and our genetic counsellors here at Igenomix, give you confidence that you are beginning your journey with science on your side.