Genetics will save the day – at least that’s the message you see pretty much everywhere in the media, and sometimes even in the academic literature. Newspaper and magazine articles herald “breakthrough” discoveries of genetic biomarkers for disorders like autism and ADHD. We read in the grocery line that a gene linked to depression has been found!
These are serious conditions, so of course parents and public health officials alike are enthusiastic about the potential of finding genetic causes. The same articles that hype these discoveries also calmly assure us gene therapies are not far behind. Genetic discovery will lead to personalized medicine and we will all be winners.
Unfortunately, the reality is much more complex. While understanding how genes influence behaviour and development is important, evidence now suggests that the genetic influence in many developmental disorders is not as significant as first imagined. We are a long way off from identifying definitive biomarkers and personalized gene therapies are likely generations away. The hype is big, but our hope is misplaced.
‘this focus on gene therapies may have distracted us’
Autism is an excellent example. It’s true that when one identical twin has autism, the chances of the second twin also having autism are increased (though not a certainty), showing a genetic connection. However, geneticists have not been able to identify a “smoking gun,” i.e., a single gene that causes autism. Rather, they have found many genes, each exerting its own small effect in a complex polygenetic interplay.
The truth is, even when specific genes are implicated, personalized gene therapies addressing multiple genes are not very likely. What’s more, this focus on gene therapies may have distracted us from using and expanding services and supports that show promise or already work for many children.
Numerous studies show that children with autism improve with intensive social-focused treatments such as speech, behavioural and occupational therapies. For decades, evidence has been accumulating about how supporting parents and providing interventions to enrich children’s educational environments can dramatically help improve developmental outcomes. Similarly, there is solid and growing evidence for psychological and social interventions, along with family supports for addressing ADHD, with solid outcomes.
We do not mean to imply that there is no genetic component to the developmental hurdles children with autism or ADHD face. But, waiting until we understand the genetic underpinnings – or funneling essential funds into genetic discovery – distracts us from investing in ordinary community strategies that can help these children and their families be successful today.
The focus should be on community support for young families with children
Let’s take depression as another example. We know that people who carry certain genes related to depression (short alleles of the serotonin transporter gene) are more likely to be depressed as teenagers and adults when they were also raised in difficult conditions, such as experiencing neglect or abuse as children. On the other hand, others with those same genotypes thrive as teenagers and adults when they had optimal early environments. This speaks to the important role of positive social conditions for these specific gene variants. On the surface, genotype seems to matter, but only under poor early environmental conditions.
So, rather than assessing children for their genotype in order to identify children at risk for this specific cause of depression, we could benefit all children, including those at risk, by ensuring that all young families and communities are adequately supported to provide their children with the best start in life.
In this example, the evidence is clear. Family and community supports such as early intervention, income assistance, group prenatal and parenting programs, perinatal home visiting and high-quality child care could protect children and youth from potentially serious behavioural and emotional problems, regardless of their genotype.
So, in a range of issues such as autism, ADHD and depression – all with long track records of distinct evidence-based social and community interventions – genetic discoveries are interesting, certainly, and worth pursuing, but do not provide the help that is needed today. Let’s save the hype for what helps families now: tried and true, social and community-based treatments.
Nicole Letourneau is an expert advisor with EvidenceNetwork.ca and the author of Scientific Parenting. Suzanne Tough is an Alberta Innovates Health Scholar. Both are professors at the University of Calgary’s Owerko Centre focused on children’s neurodevelopment.