Around 1 in 5 people diagnosed with cancer in the UK take part in a clinical trial.
A study looking at testing all Ashkenazi Jewish people for a cancer gene (GCaPPS)
This study looked at the possibility of offering gene testing to all Ashkenazi Jewish people in London. The aim of the GCaPPS research study was to find the best method of screening for risk of inherited (familial) cancer. It compared the current system of testing only those with a strong family history of cancer with the new option of testing everyone (population testing).
Genes are coded messages inside the cell that tell it how to behave. If the gene is lost, or changed due to damage, this changes the code. We know from research that alterations in the
Inherited changes in these genes are more common in Ashkenazi Jewish people than in the rest of the population. The only people currently offered testing for these gene changes are those with a strong family history of cancer. However, many people are not aware of their family history or its significance and do not seek advice. This could miss a number of people who do not have a strong family history but carry an alteration in this gene. And so have an increased risk of getting cancer or of passing these gene changes on to their children.
In this study, the researchers wanted to find out
- Whether population screening (compared to a family history based approach) finds more people with BRCA gene alterations
- If it is acceptable to people
- About possible differences in psychological impact and
quality of life
- About the cost effectiveness of both methods
Summary of results
The study team found that testing everyone with an Ashkenazi Jewish background helped to identify more people with a BRCA gene change than only testing those with a strong family history.
1,034 Ashkenazi Jewish people took part in this randomised study. They were put into 1 of 2 groups by a computer. Neither the person taking part nor the researchers could decide which group they were in. Everyone was offered detailed individual genetic counselling.
In group 1, everyone had their blood tested for the BRCA gene alterations (genetic testing). Researchers call this the population screening group.
In group 2, only people who had a strong family history of cancer had their blood tested for the BRCA gene changes. Researchers call this the family history group.
When the researchers looked at the results they found that
- In group 1 there were 13 people with BRCA gene changes
- In group 2 there were 9 people with BRCA gene changes
The researchers also looked at how people rated their quality of life and the emotional impact that genetic testing had. But they found there was no difference between the 2 groups in either of these.
The study team followed up the people who took part for 3 years. They found that 210 people in group 2 who didn’t have a strong family history and so didn’t have their blood tested in the study, decided to have the genetic test later on. When the researchers looked that these results, they found 5 more people with a BRCA gene change.
In this study, the researchers found that 15 out of 27 (56%) or over half the people carrying a BRCA gene alteration (mutation) would not have been identified or detected using family history based testing.
The researchers also looked at the cost effectiveness of testing all Ashkenazi Jewish women aged 30 years or older for changes in the BRCA1 or BRCA2 genes. The study team worked out the number of cancers and possible treatment costs for them if they were diagnosed with breast or ovarian cancer in the future. They compared the outcomes and treatment costs of population screening with the current practice of family history based screening. They found that population screening (compared to family history screening) cost a lot less.
The researchers concluded that population screening for people with an Ashkenazi Jewish background was useful, acceptable to people and helped to identify more people with a BRCA gene change. Population screening for this group of people could save the NHS money, prevent cancers and save lives in the long term.
We have based this summary on information from the team who ran the trial. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Please note: In order to join a trial you will need to discuss it with your doctor, unless otherwise specified.
Professor Ian Jacobs
Dr Ranjit Manchanda
The Eve Appeal
Academic Study Group on Israel & the Middle East
Agudas Israel Housing Association
Institute for Womens Health University College London (UCL)