Nature or nurture and the ethics of DNA testing under the spotlightWednesday 25 May 2016
Professor Mehmet Dorak’s Inaugural Professorial Lecture explored what we can – and can’t - learn about ourselves from our DNA, and how ethics should also play a big part when it comes to DNA testing.
Professor Dorak acknowledged the momentous impact that the discovery of DNA has had on us all, showing the audience an image of the 800-word journal article published in 1953 which changed the world.
He then made the point that many of our traits – including height, weight and hair colour - are not determined by a single gene.
He spoke about the interface between nature and nurture, giving the example of the Queen Bee who is not genetically different to the other bees, but who has simply fed on Royal Jelly. He also discussed epigenetics in terms of how even childhood trauma can change our genes.
Professor Dorak drew on research which argued that our genes can determine whether we are a morning person or even whether we will go bald.
He also told the audience about the great strides being made with DNA information – which includes being able to reconstruct people’s faces from a single sample.
He then went on to explore the “new and urgent” ethical issues that DNA brings, and questioned at what stage DNA should also mean ‘Do Not Ask’?, raising the issue of whether it is morally right to tell someone that their genes mean they will develop an incurable disease. Who else should know, and how, then, do you balance this with the factors that you can change?
Professor Dorak then illustrated that while genetic testing is in principal a good idea, it does come with risks, saying that “while a genetic test with 99% accuracy and only a 1% false-positive rate sounds good,” if a disease occurs in 1 in 1000 people, and 1,000,000 tests are done with 99% accuracy, this means that 990 of 1,000 people have been detected (with the disease gene) with a rate of 1% false-positivity. Ultimately, 10,000 people will have been wrongly detected as positive. Professor Dorak then put this into the context of the current accuracy of existing tests – which is around 70-75%
Professor Dorak concluded that traditionally, the emphasis has been on protein-coding genes, and on mutations changing their function, but recent findings emphasise the importance of non-coding regions of the genome. Only a few very rare, but very strong mutations can be used as deterministic biomarkers.
Most disease risk markers have very weak non-exclusive correlations, and cannot be used to assess risk with high confidence. Almost every trait has some genetic basis, but the environment almost always has a dominant effect.
He ended the lecture by telling his audience that “Genetics is not necessarily destiny. Your genes are up to chance; but your lifestyle is up to you!” and stating a recent study which said that a good social life played a major part in a long and healthy life.
This month Professor Dorak also presented at the European Federation of Immunogenetics (EFI) annual conference in Kos island, Greece. He displayed one poster and gave three presentations in three different sessions on bioinformatics in immunogenetics, evolution and disease genetics.