Genomic testing should become a normal part of NHS care, beginning with cancer patients and those with rare diseases, says the chief medical officer, Dame Sally Davies.

In her annual report, Davies stresses her enthusiasm for the genomic revolution which could transform the treatment that NHS patients receive. Drugs can be matched to the disease and to the patient to maximise the benefit and reduce side-effects.

The genome is the collection of 20,000 genes, including 3.2 billion letters of DNA, that make up any individual. We all share about 99.8% of the genome. The secrets of our individuality – and also of the diseases we are prone to – lie in the other 0.2%, which is about 3 or 4 million letters of DNA.

Davies says that individual patients have everything to gain from the pooling of data which allows scientists to compare hundreds of thousands of genomes, to find out why some have small mutations or errors in the code that lead to illness. She talked of a new “social contract”, in which the public recognises that they and everybody else will benefit if they allow data about their own genome to be studied.

“The age of precision medicine is now and the NHS must act fast to keep its place at the forefront of global science,” said Davies. “This technology has the potential to change medicine forever – but we need all NHS staff, patients and the public to recognise and embrace its huge potential. Genomic medicine has huge implications for the understanding and treatment of rare diseases, cancer and infections.”



Cancer and rare diseases are the first targets for genomic medicine. More than 30,000 people have had their genomes sequenced so far. Within five years, she would like to see genomic testing to be as normal as blood tests and biopsies for cancer patients, leading to the most appropriate treatment for the individual. Davies said she wanted to “democratise” genomics medicine so that it would be available to every patient for whom it was appropriate.

“That means we have got to change the NHS system,” she said. Genomics is at present “a cottage industry” which needed to be centralised and extended across the country. “We need to take the science to the patients and not the patients to the science,” she said.

There are great potential benefits for patients with rare diseases, defined as those affecting fewer than one in 2,000 patients. But there are at least 6,000 rare diseases worldwide and at least three million people – often children – in the UK suffer from them. Genome sequencing is also very useful in infectious diseases, allowing doctors to find out whether antibiotic and antiviral drugs will work in a patient.

Amongst her recommendations, Davies calls for a National Genomics Board to be set up, chaired by a government minister. All genomic laboratories should be centralised and a national network established to provide equal access across the country, she says.

• This article was amended on 4 and 5 July 2017. An earlier version referred to a figure from the report which said 0.2% of the genome amounted to 3 or 4 billion letters of DNA. This has been corrected to say 3 or 4 million letters of DNA. The headline has also been amended because Sally Davies is England’s chief medical officer, not the UK’s.