Carrier Screening with a Whole Genome

Message us about carrier screening, or call 020 3951 3429.

When to get help today

A genetic test is never an emergency and a symptom can be. If you have chest pain, breathlessness at rest, or you lose consciousness without warning, call 999 or go to your nearest emergency department today.

If a result has frightened you this week, speak to a clinician quickly rather than searching for more of the same online. Send us the report and someone will read it.

What carrier status means

Autosomal recessive means that two copies of an altered gene, one from each parent, are needed to cause the condition, National Human Genome Research Institute, 2026. The parents of an affected child each carry one copy and typically show no signs of it, MedlinePlus Genetics, 2026. A person with one copy is a carrier.

The Cystic Fibrosis Trust states that one in 25 people carry the cystic fibrosis gene, usually without knowing, 2026. Sickle cell disease is another recessive condition, caused by variants in the HBB gene, MedlinePlus Genetics, 2026.

The odds if both partners carry the same variant

If both parents carry the same recessive variant, each pregnancy has a 1 in 4 chance of an affected child, a 1 in 2 chance of a carrier child and a 1 in 4 chance of a child who inherits neither copy, Cystic Fibrosis Trust, 2026.

These are odds for each pregnancy and not a count. Two children in a family can both be affected, or neither, and a counselor explains what the odds mean for your family and what options exist.

Message us about my partner and me

Why use a whole genome

A whole genome reads far more of your DNA than a typical carrier panel, so one sample can be read for many conditions at once. Screening for many conditions together can identify couples at risk, a model described in Haque and colleagues, JAMA, 2016. The American College of Obstetricians and Gynecologists describes carrier screening as a way to let people consider their reproductive options, Committee Opinion 690, 2017.

You decide with the counselor which carrier findings you want reported. The same file can later be read for other questions, such as how you process medicines, without a new sample.

Who it is for

Adults who are planning a pregnancy or thinking about one, and couples who want to know before they start. It is a test for adults. We do not test a pregnancy or a newborn.

If one partner is a carrier, the other can be checked for the same condition, and a counselor explains the options. The Cystic Fibrosis Trust also describes carrier testing for relatives and partners of someone with the condition, 2026.

What it cannot do

No screening covers every condition. A result with no variants lowers the chance that you are a carrier for the conditions reviewed. It does not take the chance to zero, and it says nothing about other health outcomes in a child.

What we would do

One. A conversation with a registered genetic counselor, at no charge, before anything is taken and before you commit to anything. Bring your family history, because it changes what is worth doing.

Two. Saliva at home or a blood draw in Marylebone, sequenced at 30x in a laboratory accredited to ISO 15189.

Three. The result read with a doctor, written into your record, and read again as the evidence moves.

Start with the first conversation

Message us to book the first conversation

Questions people ask

What is carrier screening? It checks whether you carry one copy of a gene variant linked to a recessive condition. Carriers are usually healthy. One in 25 people carry the cystic fibrosis gene, Cystic Fibrosis Trust, 2026. Tiers here start at £1,695.

What are the chances if both partners are carriers? Each pregnancy has a 1 in 4 chance of an affected child, a 1 in 2 chance of a carrier child and a 1 in 4 chance of a child who inherits neither copy, Cystic Fibrosis Trust, 2026. These are odds for each pregnancy and not a count.

Do both partners need to be tested? Testing both gives the clearest picture. If one is a carrier, the other can be checked for the same condition, and a genetic counselor explains the result and the options open to you. Many couples begin with one partner and add the other if needed.

Can you test during pregnancy or test a newborn? No. This service is for adults. We do not test a pregnancy or a newborn, and if you are already pregnant and worried about a condition, we will tell you who to speak to quickly so that you are not waiting on our results.

Is a negative result a guarantee? No. It lowers the chance that you carry a variant for the conditions reviewed. It does not remove it, and it says nothing about other health outcomes in a child, so the counselor explains what a clear result does and does not mean.

Do I need a GP referral? No. You can start with a free first conversation with our team. Bring what you know about inherited conditions in either family, because that history, and your ancestry, shapes which findings are worth reporting to you.

Message us before you decide, or call 020 3951 3429.

This page is information and not a diagnosis. Sequencing does not replace examination, history or blood work, and no result guarantees an outcome. If you are unwell today, see a doctor today. In an emergency call 999.

References

Cystic Fibrosis Trust. Information for carriers. cysticfibrosis.org.uk, read 2 October 2026.

Cystic Fibrosis Trust. What causes cystic fibrosis. cysticfibrosis.org.uk, read 2 October 2026.

Cystic Fibrosis Trust. Family genetic testing. cysticfibrosis.org.uk, read 2 October 2026.

National Human Genome Research Institute. Autosomal recessive disorder, genetics glossary. genome.gov, read 2 October 2026.

MedlinePlus Genetics. Inheritance patterns, and sickle cell disease. medlineplus.gov, read 2 October 2026.

Haque IS, Lazarin GA, Kang HP, Evans EA, Goldberg JD, Wapner RJ. Modeled fetal risk of genetic diseases identified by expanded carrier screening. JAMA, 2016;316(7):734-742. 10.1001/jama.2016.11139

American College of Obstetricians and Gynecologists. Committee Opinion No. 690, Carrier screening in the age of genomic medicine. Obstetrics and Gynecology, 2017.

ISO 15189:2022. Medical laboratories, requirements for quality and competence. International Organization for Standardization.