Genetics and the Possible Causation of Autism Spectrum Disorders

In 1911, Eugene Bleuler, a Swiss psychiatrist, began using the term “autism”, which stems from the Greek word “autos”, meaning “self.” Bleuler used the term to describe a group of symptoms seem in patients suffering from schizophrenia. Essentially, the term means an “isolated self” or a person excluded from social interactions. In the 1940s, researchers in the United States modified the term to describe children who experienced emotional or social problems. Thus, relinquishing the word “autism” from it's connection to schizophrenia (Hirsh 2009, pg 1).

Today autism is described as a complex developmental disability, and the term Autism Spectrum Disorders (ASDs) is used to encompass a group of disabilities with similar features. The three categories of autism spectrum disorders are Autistic Disorder (also known as “classic autism), Asperger Syndrome, and Pervasive Developmental Disorder Not Otherwise Specified (PPD-NOS) (NICHD 2010).

SYMPTOMS

The symptoms of autism spectrum disorders can usually be observed in children at eighteen months of age. They include problems with communication, social interactions, and repetitive behavior. While some have severe ASD symptoms, others only possess mild symptoms like those suffering from Asperger's Syndrome. The variations of symptoms and severity is why autism is referred to as a “spectrum” disorder (NICHD 2010).

Communication in those diagnosed with an autism spectrum disorder proves to be difficult. Some children suffering from ASDs never babble or coo and remain mute throughout the duration of their lives, while others don't develop language skills until ages five to nine. The children and adults that develop language skills often use them in peculiar ways. Some cannot form meanin...

... middle of paper ...

...that autism spectrum disorders fit into the category of locus heterogeneity, meaning “a single disorder caused by mutations in genes at different chromosomal loci” (Genetics Home Reference 2011).

CHROMOSOMAL ERRORS LINKED WITH AUTISM SPECTRUM DISORDERS

In the search for a cause, researchers have indicated several genes and regions that may lead to autism spectrum disorders. Unfortunately, studies have not been able to conclusively pin-point which variations of chromosomal errors are the exact cause of ASDs. Further research into the following mutations will shed light on how genetics play a role in the development of ASDs: chromosome 15q11-q13 region, serotonin transporter gene, neuroligin genes, Methyl-CpG-binding protein 2 gene, Reelin gene, multiple ankyrin repeat domains 3 gene, duplications of chromosome 15q11-q13, chromosome 7, and 22q11 deletion syndrome.