Why did my child develop Autism?
This is a question I am regularly asked, understandably so and therefore I thought I would review the current evidence to give the best answer I can with all the information we have discovered to date.
Autism is a Spectrum Condition ranging from one end with children who are non-verbal with Significant Learning difficulties to the other end with academically able or gifted children but who struggle significantly with their social interaction. All of these children have the same condition but differ significantly in their presentation and range of difficulties. Just as Autism itself is a spectrum of difficulties we feel there is not one single causative factor but a spectrum of causes.
Currently worldwide 1 in 88 children are diagnosed with Autism.
Part of this increase in the number of cases diagnosed is greater awareness in Professionals, Parents and Teachers of the condition as well as widening of the diagnostic criteria.
There is no credible evidence to suggest that vaccinations are in anyway linked to the causation of Autism. The original research study which linked Autism to MMR has been completely discounted, found to be fraudulent and the Doctor involved removed from his Professional register. In fact the chemical that he felt was linked to the causation of Autism found in the MMR (Thiomersal) was discontinued from vaccinations in 1992 and despite this the incidence of Autism has continued to rise.
Some Factors that we do know about are
Advanced Paternal age (age of Father) at the time of conception.
The use of certain medications in pregnancy such as Sodium Valproate for epilepsy and some anti-depressant medications as well as a number of others. Other insults in pregnancy such as infection, significant trauma and prematurity are felt to increase the risk of developing Autism.
Certain Genes can cause Autism and we are aware that genetics plays a larger role in Autism than in Diabetes or other conditions. There may be one single gene or a combination of genes and developmental processes. These genes fit together in a pathway to affect neuronal development and processes. Around 200-400 genes are felt to be involved and that is why there is such a wide spectrum. Some cases may occur when there is no family history of Autism. In these cases 25% are due to new mutations and in 75% of cases there is no known cause.
The concordance rate in identical twins for Autism is 77%, non identical twins is 31% and in regular siblings is 20%. Therefore there are clearly other factors such as environmental factors in play in addition to genetic factors.
I feel the most important thing to stress is that Autism is nobody’s fault and it is unproductive for one parent to feel guilt / blame themselves or be blamed due to the large number of factors at play. There is a lot that we still do not know as yet but lots of work is being done in this area and hopefully we will soon have more answers on the role of individual genes and their interplay with environmental factors.