Possible Causes


There have been dozens of articles trying to connect vaccines and autism in an interlinking cause and effect relationship. These investigative write ups made by different personalities have led many individuals and families to follow through and even superimpose their own evidence to provide support for the existing theory. The notion that vaccination causes autism has spread rapidly across the globe, which stirred panic among parents of babies who then had second guesses as to the safety of vaccination for their child. But in light of this alarming threat, there are also published medical reports that presented sufficient proof to discredit the said theory. A British Journal of Medicine article, for example, has given solid ground to disprove Andrew Wakefield’s study on 1998, which is believed to be the main proponent of this theory. With this argument already invalidated and with only a few remnants of supporters left today, the medical field is still faced with the existing question as to what really causes autism.

While experts are still on the hunt for more indisputable findings, they have raised the possibility that an interplay between genetic and environmental factors could cause the occurrence of autism-related cases. These variables can act alone, but it may also be that such underlying genetic factors are triggered by the environment in which the individual is exposed to. But because the nature of autism is a spectrum disorder, manifestations of symptoms in several ways can also indicate that the ‘genes and environment’ premise can be more complex than it is and that more than one dimension of these factors could give rise to autism in an individual. For instance, the fact that each of us has different genetic makeup and the environmental conditions in which we are exposed to could also vary, it is more likely that more than these two factors can cause autism.

Genetic Factors

It is a common interpretation that ASD is an inheritable neurologic disorder, the case of which is true but not absolute. There are several known cases of parents who had another autistic child after having an autistic firstborn, with the possibility of one occurring in every 20 families according to the National Institutes of Health, a risk that is relatively higher compared to the population whose firstborn is neurotypical. Moreover, it is also found out that there’s a 9 out of 10 chance that a twin sibling will be diagnosed with autism if the other one is already known to be autistic.

However, the genes found to be causing autism are not actually inherited but are spontaneously mutative in nature which means that the occurrence of autism can happen right after fertilization, where the parents’ normal inherited genes start to undergo mutation. There are about 20 or more identified genes that are known to possibly cause autism spectrum disorder, and most of these genes have brain development functions, which could explain the nature of autism. More focused studies have identified very specific genetic mutations as very likely antecedents. For instance, a mutation occurring in chromosome 17 has 14 times higher possibility to cause autism than mutations that happen in other genetic codes.

Parents’ Age

There are also several research findings that indicate how a mother’s age when she became pregnant can be the cause of the child’s autism. Generally, the risk of having an autistic child increases relative to the age of the mother gestating, where a 40-year old mother is 50 percent more likely to have an autistic child than those who are 11-20 years younger.  However, the case cannot be isolated to mothers alone, as experts also include the age of fathers to be an equally likely factor, knowing that the creation of a child involves the merging of both sperm and egg cells. Although the cause that links the parents’ age to autism chances is still yet to be identified, it is inferred that the parents’ genes are more susceptible to mutations when they get older.


There are many studies that can provide conclusive evidence which links exposure to pesticides and autism. The chemical components present in most pesticides are said to interfere genetic development in an adverse way, where the genetic codes most susceptible to mutation are triggered hence leading to the occurrence of the neurologic disorder. Simply put, foetuses or infants that carry mutation-vulnerable genes can develop autism spectrum disorder if exposed to pesticides particles, with the level of concentration enough to trigger such mutation.


As a neurologic disorder, it cannot be denied that autism is the result of specific irregularities in an individual’s brain processes. Many research indicate that certain areas of the brain like the cerebellum and cerebral cortex are where these flaws occur, especially because they are primarily responsible for controlling body motion, the level of concentration, and mood.  When there are certain imbalances in the level of chemical messengers in the brain due to defects in some parts of the brain, these could probably result in cases of autism in an individual. There could be an imbalance in dopamine levels, which could adversely affect movement and concentration. Alternatively, if the serotonin level is unstable, the person can easily develop behavioural problems dictated by mood.

Pharmaceutical Products

Just like the chemical components found in pesticides, many pharmaceutical products taken in by a gestating mother can pose health risks to the foetus, specifically autism-related issues. Drugs that contains the substance Thalidomide have been widely recalled from the market due to the controversial findings that the said substance causes congenital abnormalities. Today, Thalidomide can be found in products prescribed for cancer patients and severe skin diseases.

Another chemical substance called Valproic acid is also identified as a possible autism-causing agent if a pharmaceutical product containing it is consumed by the pregnant mother. Drugs containing Valproic acid are prescribed to treat bipolar and mood disorders, as well as seizures. It is very important that parents, especially mothers, should always check the composition of the drugs they are to take in as they can give adverse effects on foetus’ development.