What is whole genome sequencing?

Your genome is all of the genetic information in your body’s instruction manual. It is written in a chemical code called DNA. All living things have a genome; plants, bacteria, viruses and animals. Whole genome sequencing is when all of this DNA code is read by a computer. This can then be analysed to look for changes linked to rare disease or cancer.

Great Ormond Street Hospital for Children NHS Foundation Trust produced this helpful video in consultation with school children to explain what whole genome sequencing means.

What made you choose these particular rare diseases?

There are over 8000 rare diseases and we can’t include them all. The ones chosen represent those for which there was unmet need (for instance, there is a proportion with no known genetic diagnosis) and those for which genome sequencing may offer the best opportunity to better understand the disease. We expect more rare diseases to be included throughout the lifetime of the project. A full list can be found on the Genomics England website here.

Why are there only some cancers on the eligibility list?

We have started with cancers that are common and affect a very large number of people. We will be adding other cancers in the future. A full list of eligible cancers can be found on the Genomics England Website here.

Why cancer patients who have not had treatment?

We’re sorry but you will unfortunately be unable to join the 100,000 Genomes Project if you have already started your cancer treatment (chemotherapy or radiotherapy). This is because we need to know what your genome looks like BEFORE treatment as the treatment itself may cause changes in the genome. Your hospital doctor will be happy to talk this through with you. Your NHS clinical care team may also be able to let you know about other projects you may wish to participate in.

What if I agree to participate and then decide I don't want to be in the project anymore?

This is not a problem at all. Please be reassured that you can withdraw from the Project at any time. This will not affect your NHS care in any way. Please ask your hospital doctor and your clinical care team about this.

Will taking part have any effect on insurance?

Please be reassured that data from the 100,000 Genomes Project is part of a healthcare and research Project and is not disclosed to insurers. You can read more here.

Why aren’t you including healthy people, surely you need to compare sick people with healthy ones?

This is an important point but since we are comparing cancer genomes with the healthy genome of the person affected by that cancer, and the genomes of two unaffected healthy relatives with a person affected by rare disease, we will actually have tens of thousands of ‘normal’ genomes within the study.

My baby has one of the rare diseases listed but we live in an area which does not have a GMC in the area. How do I take part?

Patients for the 100,000 Genomes Project can only be recruited through GMCs. Most areas of England have a GMC. However people living in an area which does not have a GMC can ask to be referred to their Regional Genetics Centre to discuss participating in the project.

Can we join if we are in the Deciphering Developmental Disorders DDD study/other research projects?

Participation in other research projects does not necessarily preclude joining the 100,000 Genomes Project. However if you have been invited to join the 100,000 Genomes Project by your clinician, please notify them if you are currently involved in any other research studies.

I thought infectious diseases were included too?

The infectious disease strand of this project is being led by Public Health England.

I have a rare disease and live in London but my mum and dad live in Scotland. Does this matter?


I’m interested in volunteering for genomic research, but I am not currently eligible for the 100,000 Genomes Project. Are there other studies that might be relevant?

You can find some local opportunities with the North Thames Clinical Research Network.

Where can I find out more?

Please also see the Genomics England FAQs page