Saturday, 4 January 2014

Direct to Consumer Genetic Testing (DTC-GT) and the physician’s role


Direct-to-consumer (DTC) genetic testing is a type of genetic test that is accessible directly to the consumer without having to go through a health care professional.  In clinical practice, the health care professionals are the ones requesting for genetic testing and obtain informed consent of the patient. However, for some genetic tests, consumers can obtain such a test themselves. They only have to collect a sample of their saliva in the provided test tube and send it to the DTC-GT company where the laboratory will analyze their DNA. There are a variety of DTC tests, including testing for breast cancer alleles to mutations linked to cystic fibrosis. Although the companies who develop and sell the DTC-GTs promote these tests with slogans like ‘to empower you with genetic insights to help motivate you to improve your health’, it is not expected that consumers themselves can correctly interpret the complex results. In genetic testing, the results are usually expresses as ‘risks’ to certain diseases or disorders and not a simple ‘yes or no’ outcome. In addition, these GT should be fully validated so as not to provide false-positive or false-negative results.

It is therefore not strange that consumers who have bought a DTC-GT then consult their physician for her/him to interpret the results. This provides the primary-health care physicians with quite a few dilemmas. First of all they themselves should be able to understand the type of test performed, the presented outcome and any possible consequences for the patient, which is not usual for non-geneticists. Secondly, they have to make sure the test results are valid and might have to order additional tests though the regular health care system. Thirdly, if the results indicate a high risk for a certain disease but possibly also for other diseases, is the physician obliged to report this to the patient who might not wanted to know this. So DTC-GT also put a burden on the physicians who have the moral obligation to inform patients, to treat them and to protect patient confidentiality.

As the prices of these DTC-GTs are expected to drop (DNA test are currently available for $99), physicians can expect an increase in patients who not only googled their symptoms, but might have gone an extra step and requested genetic testing. Canadian researcher Gillian Bartlett of the Department of Family Medicine of the McGill University in Montreal therefore urgently asks to develop best practice recommendations and identify the ethical, legal and social implications of DTC-GT.

The FDA has recently requested that several companies refrain from providing direct to consumer tests with health-related results, as they have not approved these tests yet.
 
 

 

Friday, 3 January 2014

Pharming for fish oil: Camelina plants produce omega-3 fatty acids


Scientists in the UK have genetically modified the Camelina plant to produce components of fish oils beneficial for cardiovascular health. Omega-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are traditionally sourced from fish, but can also be made in our bodies from another omega-3 acid called alpha-linolenic acid (ALA), found in nuts and vegetable oil. Although the richest source of the omega-3 fatty acids is fish, they themselves get the acids from their diet of smaller fishes that have eaten algae. These algae can synthesize the EPA and DHA. To obtain the EPA and DHA for human consumption, every year around a million tonnes of oil is extracted from ground up fish.

An alternative and more sustainable source of EPA and DHA has now been created by Noemi Ruiz-Lopez, Richard Haslam and Jonathan Napier from Rothamsted Resarch in the UK in the form of genetically modified Camelina sative plants. These plants, of the Brassicaceae family and usually called ‘false flax’, are already rich in ALA but have been ‘boosted’ by inserting seven genes of marine algea and other photosynthetic marine organisms into their genome. The seeds of this modified plant can be extracted and purified and the resulting oil can contain up to 12% EPA and 14% DHA. In addition to these health-beneficial fatty acids, the researchers have developed the plants in such a way that they do not contain undesirable intermediate (shorter) fatty acids. These ‘green factories’ could partially replace the current need for fish oil.

Thursday, 2 January 2014

Overview of Measle Outbreak in 2013

The following confirmed cases of Measles have been reported worldwide in 2013:

  • Australia (Queensland): 51, as reported by Queensland Health
  • USA: 159 up to August 2013, as reported by the CDC
  • UK: over 800 cases in the Swansea area, as reported by the NHS
  • The Netherlands: 2,543 cases, as reported by RIVM
  • Canada (Alberta); 42 cases, as reported by Alberta Health Services
Other notable outbreaks occurred in Indonesia (6,300 confirmed cases), Germany (1,520 cases), Turkey (7,132 cases) and Pakistan (over 30,000).
Most of these cases were in unvaccinated (82%) or incompletely vaccinated (13%) people.

In addition to the current measle outbreak, in Germany two cases of subacute sclerosing panencephalitis (SSPE), a rare, late complication of measles have been reported in 2013. SSPE occurs in general about seven years after having a measles infection. The CDC reports that it SSPE concerns a "progressive deterioration of behavior and intellect, followed by ataxia (awkwardness), myoclonic seizures, and eventually death." There is currently no cure for SSPE or measles, but both can be prevented by vaccination.