Ministers have struck a deal to extend a moratorium on the use of genetic test results to deny people insurance.
Blood tests could reveal future diseases
The current agreement with the Association of British Insurers was due to run out next year.
But Health Secretary John Reid announced on Monday the moratorium would be extended to November 2011.
Ministers hope the deal will reassure people who might be put off taking a test for fear the results could prevent them obtaining insurance.
At present, few predictive genetic tests are available, but it is likely that many more will soon come on stream.
Their use could potentially help save lives.
Predictive genetic tests
At present, there are only two or three predictive genetic tests that are of interest in insurers
Two look at the BRCA1 & BRCA2 genes, involved with inherited breast and ovarian cancer
The other looks at the HD gene, involved with Huntington's disease
The new framework will mean that at present the only people who will have to disclose their test results are those who have undergone a test for Huntington's disease, and who are seeking life insurance cover for more than £500,000.
The Huntington's test is currently the only one approved by the government's Genetics and Insurance Committee (GAIC).
Insurers will be able to ask for the results of any future tests also approved by the GAIC.
But any life insurance policy for less than £500,000, and any critical illness or income protection policy for less than £300,000 will be exempt.
Currently, 97% of policies are for cover less than these amounts.
In addition, genetic tests taken as part of a research study will not have to be disclosed to insurers.
This will ensure that insurance worries will not affect patient recruitment to scientific trials.
Life saving tests
Dr Reid said: "Choosing to have a predictive genetic test can be life saving, and nobody should be put off having such a test because of fears it will be used against them by insurers.
"Genetic tests that may predict disease have only recently been developed, but this framework sets out a stable and sensible environment to help support the future development of genetics."
Mary Francis, Director General of the Association of British Insurers, said: "The Concordat will provide welcome clarity and reassurance for both insurance companies and our customers, well in advance of the end of the current agreement next year.
"Because the existing moratorium works well, and the number of people currently taking relevant tests remains low, we felt confident about proposing to the government that it should be extended. "
Antonia Bunnin, of the charity Breakthrough Breast Cancer, welcomed the new agreement.
She said: "This news will be a great relief for women with a family history of breast cancer.
"Our research shows that nearly a third of these women would not take the genetic test if insurance companies were able to access this data, potentially putting their health at risk.
"Choosing to take a genetic test is a difficult enough decision to make without the added fear that insurance companies may use this information against them."
Alastair Kent, Director of the Genetic Interest Group said: "Our members and their families will be able to make decisions on whether to have predictive genetic tests without fear of the insurance consequences."
Helena Kennedy, of the Human Genetics Commission, said: "Those who are affected by genetic conditions should not feel excluded from the normal benefits of society which include access to life insurance.
"Our consultations have shown very real public concern about the issue of genetics and insurance.
"These have shown that some people are put off taking genetic tests by the fear that they may be seriously disadvantaged as a result.
"I hope that the extension of the moratorium goes some way to reassure the public about these concerns."
The Department of Health has recruited ten GP posts throughout the country to provide education and advice about the use of genetic tests to staff and patients.