Articles

Future proof: What parents need to know about genetics 

8 minutes

Our understanding of genes could lead to a better understanding of medicine and disease, but how soon could new developments affect your child?

  • GM foods seem to be safer than you might think
  • DNA tests are popular, but lifestyle still has the greatest impact on your disease risk
  • Gene editing could revolutionise how we treat disease

What parents need to know about genetics

In this article, we’ll talk about genetically modified (GM) food and ask whether mapping and editing our genes could aid our children’s future health concerns.

Does GM food affect our children?

Although a lot of genetic research is still locked down in the lab, one thing that’s already out there is genetically modified (GM) food. But what does it mean for you and your family?

In the UK, we aren’t exposed to as many GM foods as some other countries, such as the United States. In fact, GM crops aren’t grown in this country at all right now and no fresh GM fruit or vegetables are currently approved for consumption by humans within the EU. However, you’re likely to be eating meat, milk and eggs from animals fed with GM crops [1].

Even if things change, the good news is that the overwhelming body of research points in favour of GM foods, suggesting that they’re doing no harm to our bodies. The Nuffield Council on Bioethics states that “the current evidence from safety assessments of GM crops does not suggest any significant risks to people who eat them [2].”

There are other issues at stake though, unrelated to health. Some people think that genetically modified organisms could interbreed with wild varieties, reducing biodiversity and affecting the environment. They’ve also been linked to a greater use of chemicals in agriculture [3].

Mapping genes to predict our future health

Interest in personal genetics is soaring, with companies such as 23andMe marketing easy-to-use DNA testing kits to consumers. While such companies promise that these tests could reveal what’s hidden in your genes, many experts aren’t convinced that they’ll help you manage your family’s health.

“I think it's important to stress that tests like these are in no way diagnostic,” says Dr Niamh O'Sullivan, Head of Genetics at University College Dublin. “They cannot tell you – for the vast majority of things that are likely to affect you in your life – whether or not you're going to actually get a disease. Lifestyle choices can have a much greater disease risk than genetics.”

The Alzheimer’s Society agree, arguing that genetic tests for genes linked to dementia are not accurate ways of predicting whether someone will develop the disease [4]. They are also concerned that people taking commercial DNA tests aren’t offered any genetic counselling to help them understand the results.

But, with scientists discovering more every day, genetics is set to play an ever-greater role in our lives. For our children, genome mapping could one day be commonplace.

“Within the next 15 years we are going to be using genome sequencing to help us in the diagnosis and treatment of all sorts of conditions,” argues Dr Saskia Sanderson, Senior Research Fellow at the Institute of Health Informatics at University College London. “Do you want to have your genome sequenced? When that question comes, you will have to weigh up the benefits and the harms and make a decision that is right for you.”

 

Genome sequencing raises some interesting ethical questions about the potential impact that the results are going to have on individuals. It’s tricky to predict how people will cope with the results and whether they will understand enough to act positively on them. But the hope is that genomic information is going to empower people to reduce their risk of disease.

Gene editing to wave diseases farewell?

But forget for a minute the idea of understanding our genes – what if our children could go one step further and change the genes they were born with?

With a lab technique called CRISPR, scientists can change gene sequences by adding,  replacing or removing sections of DNA. In 2017, a UK team used leftover IVF embryos to disable a gene thought to play a role in early development. They hope their research will reveal why some embryos don’t survive and help prevent miscarriage.

“CRISPR is like the smartphone of science,” says Dr Helen O’Neill, a molecular geneticist at University College London. “By updating our technology, we can maybe look to cure some diseases – for the majority of genetic disorders and cancers and diseases there is no cure. It could work in two ways: One way is to treat a person who's already sick, the other is to prevent the illness in the first place.”

But gene editing isn’t just for humans. Your children could one day be living in a world free of diseases such as malaria, thanks to so-called ‘gene drives’. Scientists have already modified mosquitoes in the lab with a mutated gene that makes females infertile [5]. Released into the wild, this would rapidly cut the population and reduce cases of malaria. The idea remains controversial.

At this stage, genome editing with techniques like CRISPR isn’t reliable. Some research is showing that it can cause unpredictable damage to cells, which could result in unsafe side effects [6] . There’s still lots more research to be done.

Few would argue that advances in genetics aren’t going to affect your child in the future.

“But the fact of the matter is we're absolutely not defined by our genes,” says Niamh. “We know this to be true because identical twins who are genetic clones are not identical people.”

The best thing you as a parent can do is encourage your child to be interested in science so that they can make informed decisions when the time comes.

Sources

[1] The Royal Society, 2016. Where are GM crops being eaten? https://royalsociety.org/topics-policy/projects/gm-plants/where-are-gm-crops-being-eaten/

[2] Nuffield Council on Biogenetics, 2014. Concerns about GM crops. http://nuffieldbioethics.org/report/gm-crops-developing-countries-2/concerns-gm-crops, chapter 4

[3] World Health Organization, 2014. Frequently asked questions on genetically modified foods. https://www.who.int/foodsafety/areas_work/food-technology/faq-genetically-modified-food/en/

[4] Alzheimer's Society, 2015. Alzheimer's Society's view on genetic testing. https://www.alzheimers.org.uk/about-us/policy-and-influencing/what-we-think/genetic-testing

[5] Kyros Kyrou, Andrew M Hammond, Roberto Galizi, Nace Kranjc, Austin Burt, Andrea K Beaghton, Tony Nolan & Andrea Crisanti, 2018. A CRISPR–Cas9 gene drive targeting doublesex causes complete population suppression in caged Anopheles gambiae mosquitoes. Nature Biotechnology, https://www.nature.com/articles/nbt.4245

[6] Wellcome Sanger Institute, 2018. Genome damage from CRISPR/Cas9 gene editing higher than thought, https://www.sanger.ac.uk/news/view/genome-damage-crisprcas9-gene-editing-higher-thought