The company that makes the world's biggest-selling gene test for breast and ovarian cancers is refusing to share groundbreaking knowledge that could benefit patients, academics claim.
Myriad Genetics is accused of deliberately withholding data that could help other scientists to understand cancer genetics, on the grounds that the information is commercially sensitive.
The healthcare company manufactures the test for determining whether women carry potentially lethal mutations of the two genes linked with inherited forms of breast and ovarian cancer. It has a monopoly on the tests in the United States and is about to start more aggressive marketing in Europe.
"We are very concerned that such important data is being withheld from those who need it," said Professor Martina Cornel, chair of the European Society of Human Genetics policy committee.
While Myriad is refusing to let other scientists have access to its data, the company has free access to the public databases compiled by other scientists, Professor Cornel said.
"Myriad's stated aim to enter the European market more vigorously may lead to unfair competition with academic institutions for predictive precision," she said.
"It is vital that progress towards personalised medicine, which holds out so much promise, is not hindered by companies maintaining private genomic databases."
In addition to testing for the cancer-causing mutations on the two BRCA genes, Myriad uses its tests to compile a database of other mutations known as "variants of unknown significance" (VUS) which it gathers from patients and their family members.
The company initially stopped sharing this information with other researchers in 2004 because of difficulties in matching data formats. However, in 2005 it adopted a deliberate policy of retaining the data as a trade secret, according to a study led by Robert Cook-Deegan of Duke University in North Carolina, a former member of the US Office of Technology Assessment.
Since then, Myriad has refused to share data on BRCA gene variants – which is normally done by placing the information in public databases – on the grounds that the data is proprietary information gathered as a result of its BRCA Analysis tests, on which it retains the patent rights.
"Current practices of proprietary databases may hinder interpretation of genomic data and impede the advance of personalised medicine," says the study, published in the European Journal of Human Genetics.
"Myriad clearly sees its proprietary database as a source of competitive advantage, one that will persist after its underlying patents expire or are invalidated in court," it adds.
Sharing the information on the VUS is important because it helps doctors correctly to interpret the results of a breast cancer test, the researchers said. Building up a database could be the reason why Myriad finds only 3 per cent of its tests fall in to the VUS unknown category, they said, while the tests in the hands of European testing services report a 20 per cent VUS rate, they said. Professor Cornel added: "Interpreting the variants of unknown significance that may be found on analysing the patient's genome plays an essential part in being able to provide proper counselling and if necessary preventative or therapeutic guidance.
"We know that, regrettably, medical geographic inequalities are common. But what is particularly worrying about this situation is that it is the first time that such inequalities have been based on a lack of access to clinical information, rather than lack of a product."
David Scott, director of science funding at Cancer Research UK, said that the charity has funded a wide spectrum of research into cancer genes, the results of which are publicly available to researchers around the world.
Dr Scott said: "The availability of large sets of data containing the identity and frequency of mutations in populations could help to speed up scientists' understanding of cancers and their risk factors – potentially enabling the development of new ways to diagnose and treat cancer in the future."
A spokesman for Myriad Genetics, which is based in Salt Lake City in the United States, was unavailable to comment.
Myriad Genetics: A history
Myriad Genetics has been at the centre of the controversy over gene patenting and the sometimes bitter squabble between public and private genomic science. Its founders include two professors, Mark Skolnick, 66, of Utah University, and Nobel laureate Walter Gilbert, 80, of Harvard University.
The search for the gene involved in inherited forms of breast cancer, which accounts for about 5 to 10 per cent of cases, was a competitive affair in the early 1990s, with teams on both sides of the Atlantic making important breakthroughs.
When Professor Skolnick identified and sequenced the gene, he and his company, Myriad, applied for patents and the control of royalties on any gene tests resulting from the discovery. Some scientists argued that Myriad could not have done it without the work of others who made their results public.
In the second quarter of 2012 alone, Myriad generated sales of over $105m (£65m) from its BRCA analysis test.