A study looking at testing all Ashkenazi Jewish people for a cancer gene (GCaPPS)

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 (peer reviewed ) and published in a medical journal. The figures we quote above were provided by the trial team. We have not analysed the data ourselves.