A group of academics has accused Myriad Genetics, the US biotech company that holds patents on the BRCA1 and BRCA2 genetic tests for increased risk of breast cancer, of keeping secret clinical data obtained from the tests by saying the information is commercially sensitive. The paper, published in the European Journal of Human Genetics, says this practice could raise the costs of BRCA1/2 testing and make some results more difficult to interpret.
'Interpreting the clinical significance of genomic information depends on broad access to DNA sequence variants and clinical information about those tested', said lead author Professor Robert Cook-Deegan, Sanford School of Public Policy, Duke University, USA. The paper argues that such is the importance of interpreting BRCA1/2 tests accurately, information that enables researchers to do this should be shared and made freely available.
Analysis of the BRCA1/2 genes can lead to unknown mutations being picked up, known as 'variants of unknown significance' (VUS), making the results of tests difficult to interpret. However, understanding VUSs can improve the validity of test results and be of real benefit to users.
'Interpreting the VUS that may be found on analysing the patient's genome plays an essential part in being able to provide proper counselling and if necessary, preventive or therapeutic guidance', explained Professor Martina Cornel of the European Society of Human Genetics, who was not involved in the paper, voicing her concern that data is being withheld.
'By not sharing their data on the VUS obtained from individuals undergoing BRCA1/2 testing, where Myriad is the sole commercial provider of a test in the [USA], geneticists have been unable to develop the up-to-date algorithms that are necessary to best interpret the effects of genetic variants', said added.
Professor Cook-Deegan explained that when Myriad finds a VUS it offers the patient's family members free testing in an attempt to determine that variant's significance. 'Myriad collects data regarding the clinical outcome associated with that VUS, and a VUS may ultimately be reclassified as deleterious or neutral as more is learned; conversely, deleterious or neutral mutations are occasionally reclassified as VUSs', he said.
Myriad's data on the BRCA mutation is becoming more important that its patents on the tests, says Nature News Blog. Only three percent of Myriad's tests result in a VUS, compared with 20 percent for most other BRCA1/2 tests. 'This discrepancy is at least in part to Myriad having sole possession of the information needed to interpret VUS results', said Professor Cook-Deegan.
The company stopped submitting data of its BRCA tests to public databases in 2004, claiming difficulties with matching data formats. 'Since then its contributions have essentially stopped', he said.
But Professor Cook-Deegan, a former member of the US Office of Technology Assessment, said that even if Myriad's patents are invalidated by the courts (the latest ruling in the long standing litigation was by the US Federal Circuit Court of Appeals to uphold them; reported in BioNews 669), unless the data to interpret the BRCA1/2 genetic tests are made publicly accessible, then competing test providers must either send their samples to Myriad for analysis or produce 'inadequate interpretations based upon incomplete public data and algorithms'.
'They haven't done anything illegal, they found a hole that no one else thought of and built a business model around it', he said. The paper argues that policies to encourage data sharing should be introduced to deal with the perceived problem. It suggests that databases listing genetic mutations could mandate genetic test providers to share data as a condition of listing their tests. Or that regulators, insurers or national health systems could be in a position to mandate the sharing of genetic test results.