New guidance for Britain’s 150,000 practising doctors could remove the right to confidentiality from patients with inherited diseases.

When a patient is found to have a gentic disease, such as certain forms of cancer, doctors will be obliged to inform relatives about potential risks to their health, the General Medical Council (GMC) says.

Updated guidance on confidentiality, seen by The Times before publication on Monday, suggests that most patients will readily share information about their health with their children and close relatives.

However, in circumstances where family relationships have broken down, where children have been adopted — or patients refuse consent to disclosure — doctors should still share information with others who might be at risk if they remain ignorant of a potentially life-threatening condition.

Genetics is predicted to become an increasingly important branch of medicine as the underlying causes of more and more diseases are linked to an individual’s family history.

When a patient is found to have a disease caused by an inherited mutation, his or her children, siblings and even parents may also be at risk.

Knowledge of someone’s condition could lead to other family members having mutations or risks diagnosed early, giving them a better chance of prevention or survival.

Despite calls from some campaigners for a change in the law, adopted children do not have a legal right to learn details of their biological relatives’ health records, even if such details are relevant to their own future health.

The GMC’s guidance says that practitioners should balance their duty to keep sensitive medical information private against the duty to help to protect others from serious harm.

“A patient might refuse to consent to the disclosure of information that would benefit others,” the guidance states. “In these circumstances, disclosure might still be justified in the public interest.”

Henrietta Campbell, the former Chief Medical Officer for Northern Ireland, who chaired the working group that drew up the guidance, said that it “makes clear that, in the first instance, doctors should explain to a patient if their family might be at risk of inheriting a condition.

“In those circumstances, most will readily share information about their health. However, if a person refuses, it is the responsibility of the doctor to protect those who may be at risk.”

Frances Flinter, a consultant in clinical genetics at Guy’s and St Thomas’ Hospital, South London, whose service covers four million patients in the South East, said that doctors could trace any affected relatives through the NHS if given a name and date of birth.

They could then get in touch with them indirectly, if necessary without revealing specific identities, by way of a relative’s local GP. This was especially important if patients were nearing the end of their lives or were not able to pass on the information themselves, she said.

“Doctors should only think of passing on information without someone’s consent, if at all, if it has direct health benefits. This is an increasingly important topic as it’s far more common to have families scattered all over the country now, and a GP is unlikely to know the extended family personally,” she said.

“We do see cases, maybe once or twice a year, where people cannot, or do not want to, share their information. In that case, we don’t need to reveal who in the family has been diagnosed. It may be a distant relative or someone the patient has never met,” she said. “Some relatives also don’t want to be screened or find out more, but at least by being contacted, patients can make that choice.”

After pressure from the Government, police and hospital emergency services, the guidance also advises doctors to inform police whenever they treat patients who have been attacked with a knife. Police are already informed about gunshot wounds.

It also provides advice for reporting concerns about patients to the Driver and Vehicle Licensing Agency (DVLA), when, due to ill health, a patient might be unfit to drive.

Statistics behind the need to know

Huntington’s disease Fatal and incurable neurodegenerative disease caused by a dominant mutation that invariably causes disease. Anyone with a parent or sibling with condition has a 50-50 chance of having inherited the gene

Cystic fibrosis Severe and incurable lung condition. Caused by a recessive mutation, so two copies must be inherited, one from each parent, for it to develop. Siblings of CF patients have high chance of beingcarriers

Haemophilia Blood-clotting disorder caused by a mutation on the X chromosome, so usually inherited by boys. Brothers of boys with X-linked conditions have a 50-50 risk of the disease

Breast cancer Some cases caused by mutations in the BRCA1 and BRCA2 genes, which each raise lifetime risk to 60-80 per cent. Women with an affected mother or sister have a 50-50 chance of having inherited the mutation. Some carriers opt for a mastectomy

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