Direct-to-consumer genetic tests can enhance patient care – but they also come with a set of risks that should be considered
Concerns surrounding direct-to-consumer genetic tests have been highlighted in this month’s issue of Australian Prescriber.
Easy access and affordability have resulted in continued consumer interest, with such tests being promoted through community pharmacies, other retailers, by mail order or via the internet.
But although consumers using them may feel they are taking charge of their own health, such tests can often be overly enthusiastic in their promotions or even convey a false or misleading impression regarding the usefulness of the test.
Pitfalls of DTC genetic tests
In the article ‘Retail genetics’, Dr Ken Harvey and Dr Basia Diug from Monash University say that direct-to-consumer tests usually have no involvement of a medical practitioner when they are ordered.
“Some GPs have expressed disquiet at receiving test results they have not ordered and the interpretation may be difficult,” they say.
Even genetic specialists have a hard time interpreting the results: a 2012 study revealed only 7% of Australian genetic specialists reported they would be confident in interpreting and explaining the results of such genetic tests.
The National Health and Medical Research Council (NHMRC) says there is a need for caution for individuals opting to undertake direct-to-consumer genetic testing.
“Different genetic testing companies have sometimes been found to return different interpretations of the same DNA sample,” it says.
Unexpected findings or unclear results can then cause worry and confusion in patients who are not being guided by an appropriate medical professional.
Many consumers are also unaware that the generic profiles are produced through these tests may impact on family members, potential employment and life insurance.
“While private health insurance companies do not require consumers to undertake tests to assess the risk of disease, and premiums are not affected by the genetic test results, you are required to disclose information that may impact your insurability,” say Dr Harvey and Dr Diug.
“Underwritten life insurance products, including cover for life, trauma, disability and income protection which may be required for business and bank loans, could be impacted by a genetic test result.”
Currently direct-to-consumer profile tests developed in-house are not yet subject to regulatory scrutiny – however the TGA is set to change this through new standards beginning July this year.
From July 2017 relevant laboratories will be required to maintain accreditation and have their tests meet performance standards.
Benefits of genetic tests
Experts admit that genetic profiles do have the potential to help in the healthcare space, with the appropriate regulation in place.
Dr Harvey and Dr Diug say preventive care is one area where a patient’s family history and genetic profile may be able to inform care.
In another Australian Prescriber article published this month, Professor Andrew Somogyi from the University of Adelaide and Professor Elizabeth Phillips from Murdoch University argue that pharmacogenomic testing also holds great promise.
The effectiveness and safety of a drug dose is influenced by several patient factors including genetic factors, making pharmacogenomics testing an “inexpensive, relatively fast” tool to optimise drug therapy and enhance patient care.
Pharmacogenomic information can be obtained by accessing international Australian testing companies, either directly or through a pharmacy.
However Professor Somogyi and Professor Phillips agree that there is a clear need for an overarching regulatory framework and improved education for GPs, specialists, pharmacists and other healthcare professionals.
“National regulation of pharmacogenomics testing with specific reporting and interpretation templates is needed before direct-to-consumer testing by multiple provders creates confusion for patients and their health professionals.
They are also in agreement with Dr Harvey and Dr Diug that there needs to be more education of health professionals.
What should pharmacists do?
Professor Somogyi, who is Professor in Clinical and Experimental Pharmacology at the University of Adelaide, says pharmacists need to know that direct-to-consumer genetic tests are not totally comprehensive.
“The tests do not cover some of the important life-threatening severe drug reactions,” he tells AJP.
“Examples include those impacting on allopurinol and carbamazepine toxicity.
He says some of the tests only cover genes that are common in Caucasians but which might be rare in specific ethnic populations; while others that are rare in Caucasians but common in specific ethnic populations may not be tested.
“[Pharmacists] also need to be very careful about interpretation of the test, which is sometimes not adequately reported. Whether it should be reported in terms of which drugs should not be used or the dose altered, and by how much, is very much patient specific.”
Pharmacists should be liaising with the patient’s GP or specialist, who should be directing whether the test should be done or not, says Professor Somogyi.
“It’s basically a pathology test. We do not want patients getting the results and then worrying that are a poor metaboliser and they interpret that as a poor metaboliser of all drugs – when, in reality, it is only a relatively small number of drugs,” he says.
Some companies that sell pharmacogenomics tests pay pharmacists to collect the test and interpret the result for the consumer.
Pharmacists who sell genetic tests are then working under the assumption that they have a good knowledge of and should be able to interpret the test for their patient to whom they have sold the product, says Professor Somogyi.
“By selling the product, pharmacists have a responsibility to ensure the advice they give the patient is rational and sensible – remember, ‘first, do no harm’,” he emphasises.
Patients should discuss the usefulness of any tests with their doctor before paying for it, say Dr Harvey and Dr Diug.
The NHMRC says medical investigations should only be ordered where tests are reliable, where there is a professionally identified clinical need, and where clinical utility and effectiveness have been established.