‘Why did my child develop Autism?’ It’s a question often asked by parents who have a child with the developmental disorder. As physicians, we try to address that question throughout our practice, but Autism, in fact, is not a single condition; it is a spectrum of disorders. At one end we have a child who is non-verbal and cannot speak, so he uses technology to communicate his thoughts and his concerns, and if he gets upset enough, can become violent towards others or him/herself. At the other end of the spectrum, we have a child who is quite remarkable and gifted in mathematics, yet, when it comes to trying to have a conversation or being social, these things are more difficult to him than others. What becomes confusing to many parents, is that both of these children have the same diagnosis of Autism Spectrum Disorder (ASD).
One of the concerns is whether or not there really is an epidemic of autism; these days, one in 88 children will be diagnosed with autism. The data shows an increase in prevalence at the turn of the 21st century. Is this a case of an increase in prevalence over time, or is it because we have now started labelling individuals with autism by simply giving them the diagnosis when they were present before the criteria for diagnosis even evolved? In fact, at the latter part of the 20th century, legislation was passed in the United States (US) that actually provided autistic individuals with resources and access to educational material that would help them. With that increased awareness, more parents, paediatricians and educators learned to recognise the features of autism and as a result, more individuals were diagnosed and got access to the resources they needed. In addition, the definition has changed and evolved over time that now has a broader spectrum for the diagnosis.
When we compare autism with other conditions that we are familiar with, for example, cancer, heart disease and diabetes, genetics seems to play a larger role in autism than it does in any of these other conditions. However, it is not clear if one gene or a combination of genes are responsible.
In fact, in some individuals with autism, it is one single determinant gene that causes the condition. In other individuals, however, a combination of genes in part, with the development process, ultimately determine that risk for autism. We do not know in any one person, which of those two answers apply and so research started digging deeper. How then do we identify what those genes are?
Certain individuals can have autism for a reason that is genetic, but not because autism runs in the family. This is because, in certain individuals, genetic changes can take place through mutations not passed down from the parents. Such mutations can take place in the egg or sperm at the time of conception, but have not been passed down from generation to generation within the family.
We can now use that information to understand and identify those genes causing autism in those individuals. With current research it was found that 25% of cases were due to a single gene and 75% of cases were due to 200-400 genes that can cause Autism. This explains in part why we see such a broad spectrum in terms of its effects. Although there are that many genes, there is some method to the madness. It’s not simply random, but these 200-400 genes fit together in a pathway or network that starts to make sense in terms of how the brain functions. We are beginning to understand how these genes work together to determine neuronal function and interaction and how they control behaviour, both in autistic individuals and individuals without autism.
Early diagnosis is key. Being able to make that diagnosis in a susceptible individual at a small window period gives us the ability to transform and be able to impact on the growing and developing brain and this is critical.
Today, with all this research, we are now able to take infants and use bio markers such as eye contact and eye tracking to identify an infant at risk. Being able to screen on a very large scale will be very helpful in terms of being able to intervene at an early stage when we can have the greatest impact. Intervention can include medications, educational strategies and new technologies (like devices) to train the brain and make it more efficient. Yet, there is still a long way to go.
As much as we know, there is so much more that we do not know. There is the need to use, as a community, our collective wisdom to be able to make a difference.
For more information on ASD please log on to the Autistic Society of Trinidad and Tobago’s Facebook page: https://www.facebook.com/autisticsocietytt/