A word of caution about DNA testing

At the weekend I was drawn to a short item in The Observer magazine entitled Our Endlessly Fascinating Selves, under the weekly feature heading Inner Life.  It was about how our DNA makes each one of us, even identical twins, a unique individual and that the inheritance patterns of even something like eye colour, long thought to be pretty straightforward, are now being found to be much more complex.  Apparently it is effectively impossible to predict the colour of a child’s eyes, based on their parents’ eye colour and every combination is now possible, including blue-eyed parents making brown-eyed children.  The more that is known about the human genome, the more complex who we are (simply from a DNA perspective, let alone anything else) turns out to be.  This made me think about how the now widely available – and increasingly being taken up – option of DNA testing has the potential to lead people down a path of linear thinking that may not necessarily be helpful.

Most of us long for narrative simplicity in our lives; a simple line of cause and effect.  And in the words of the article,  this leads us to be “culturally programmed to misunderstand genetics.”  The truth is that human variation is infinite and just because we might discover that our DNA shows a pre-disposition to a particular disease process (increased risk of blood clotting in my case) it does not mean that I will develop this, because many other genes, plus my life-style and experiences will influence that tendency.  And, perhaps more controversially, just because we find a link to someone who shares some of our DNA, does not mean that we will be like them in any way.  Just as parents of donor conceived babies are always amazed by people who say how like the non-genetic parent they look, we often see what we want to see or assume must be there.  That old longing for simplicity.

Adam Rutherford, the author of the article is very sceptical of DNA testing, likening it at worst to a form of astrology, but he recognises the allure to test as part of our craving for simple answers to complex questions.  However, as he refers to family trees as being ‘elegantly easy to understand’ I suspect he has never considered donor conception or even, it would appear, bothered to take into account the people who have always appeared on family trees who do not share a blood line.

I absolutely do not regret taking a DNA test and totally understand why donor conceived people feel the need to do so, but I do think Rutherford has touched a raw spot about the very human wish for things to be straightforward. I enjoyed his description of the human genome as an “epic sprawling saga that culminates in you.”   An excellent reminder that life, at a cellular as well as a social level,  is nearly always much more complicated than we would like it to be.

A Brief History of Everyone Who Ever Lived by Adam Rutherford, published 8th September.



About oliviasview

Co-founder and now Practice Consultant at Donor Conception Network. Mother to two donor conceived adults and a son conceived without help in my first marriage.
This entry was posted in Uncategorized. Bookmark the permalink.