Gene testing should be common part of cancer care

England's chief medical officer has argued that DNA tests should be routinely offered to cancer patients to assist them in selecting the most appropriate treatments.

In her annual report, Professor Dame Sally Davies expressed her vision for whole genome screening (WGS) to become as standard as blood tests and biopsies, and for her ‘genomic dream’ to be realised within five years.

Humans have about 20,000 genes, with errors in DNA coding causing illnesses, such as cancer. WGS can reveal these errors by comparing tumour and normal DNA samples from the patient, with Davies suggesting that this information can then improve their diagnosis and care for about two-thirds of patients.

With more specific testing, more targeted treatment can be given with doctors offering the drugs mostly likely to be effective. WGS, which costs approximately £700, can also show which patients are unlikely to benefit, so they can avoid having unnecessary drugs and unpleasant side-effects.

Doctors are already using genetic tests to identify and better treat different strains of the infectious disease tuberculosis. Over 31,000 NHS patients, including some with cancer, have already had their entire genetic code sequenced.

At present, genetic testing of NHS patients in England is done at 25 regional laboratories - but Davies wants this to become a centralised service, with a national network ensuring equal access to the testing across the country.