A landmark study looking at all adverse drug reactions ever recorded in Britain since 1964 reveals just three genes could be responsible for many of them – and a simple test could save lives
The NHS could roll out a simple DNA test to predict and prevent dangerous drug reactions and save thousands of lives. A landmark study has identified three genes that impact how the body processes medication that could be checked for with a saliva or blood test.
Scientists behind it are calling for the NHS to routinely check if patients have these genes before prescribing them certain drugs. Previous research has shown adverse drug reactions (ADRs) cause around one in every 15 acute hospital admissions and over 5,000 deaths each year in England alone. Potentially fatal drug reactions are much more likely in older people who are living with more than one health condition. One in ten pensioners take at least eight different prescribed medications weekly.
The world-leading study has collected data on over a million dangerous reactions to drugs reported in Britain since 1964.
Co-auther Professor Sir Mark Caulfield said: “This is the largest analysis of the potential role of pharmacogenomics in adverse reactions from a national spontaneous reporting system. It suggests that 9% of these reports may relate to our genetic make-up. This could be avoidable if we had measured the genetic make-up of the person before prescribing these medicines. It is time for the NHS to consider adopting pre-emptive testing for known genes that interact with medications.”
Britain’s Yellow Card Scheme was established in 1964 in response to the thalidomide disaster. The use of the drug thalidomide to treat morning sickness in pregnant women resulted in thousands of babies being born with severe birth defects, including severely deformed limbs.
The voluntary system managed by the Medicines and Healthcare products Regulatory Agency (MHRA) allows medics, patients and parents to report suspected ADRs.
Not all reactions are picked up in clinical trials when drugs are being developed and the scheme is the cornerstone of drug safety surveillance in the UK.
It has collected over one million reports and this unique data has been used by scientists to make the discovery that 9% of all reported ADRs are associated with medications where side effect risk is partly dependent on the patient’s genes.
Of this subset of ADRs three quarters were associated with only three genes. The research team at Queen Mary University of London insist genetic testing before prescribing could therefore help avoid ADRs in these cases.
Study lead Dr Emma Magavern, of Queen Mary’s Centre for Clinical Pharmacology, said: “It is important to understand the landscape of side effects reported nationally over the past half century to elucidate the impact that prospective use of genetic testing to personalise prescribing may have in the UK.”
Previous studies have indicated that more than 99% of people have genetic variants which could lead to ADRs which cause further health problems, longer hospital stays, or even death. The cost of ADRs to the NHS is estimated to be more than £2 billion a year.
ADRs are typically described in two groups. Type A reactions are relatively common and can be dose-dependent – meaning they may not happen if someone had been given a lower dose. Type B reactions are more likely to be fatal and happen when someone’s body cannot tolerate a certain combination of drugs.
June Raine, chief executive of the MHRA, said: “This study shows how reports of suspected side effects to the Yellow Card scheme can help us better understand and prevent serious side effects, including those linked to genetic factors. The MHRA Yellow Card scheme collects reports of suspected side effects from patients, the public and healthcare professionals and plays an important role in monitoring the safety of medicines in the UK.”
The Yellow Card Scheme has partnered with Genomics England and the UK Biobank to build a dataset combining reports with the genetics of the patient. To report a suspected ADR to the Yellow Card scheme visit yellowcard.mhra.gov.uk, download the Yellow Card app or call 0800 731 6789.
