What is Autism?
Autism, or autism spectrum disorder, refers to a range of conditions characterized by challenges with social skills, repetitive behaviors, speech and nonverbal communication, as well as by unique strengths and differences. Autism is caused by different combinations of genetic and environmental factors. Some children with autism show hints of future problems within the first few months of their life. In other cases, symptoms may not become obvious until 24 months or later. Some children with autism appear to develop normally until around 18 to 24 months of age and then stop gaining new skills and/or start losing skills.
Possible signs of autism in babies and toddlers:
- By 6 months, no social smiles or other warm, joyful expressions directed at people
- By 6 months, limited or no eye contact
- By 9 months, no sharing of vocal sounds, smiles or other nonverbal communication
- By 12 months, no babbling
- By 12 months, no use of gestures to communicate (e.g. pointing, reaching, waving etc.)
- By 12 months, no response to name when called
- By 16 months, no words
- By 24 months, no meaningful, two-word phrases
- Any loss of any previously acquired speech, babbling or social skills
Possible signs of autism at any age:
- Avoids eye contact and prefers to be alone
- Struggles with understanding other people’s feelings
- Remains nonverbal or has delayed language development
- Repeats words or phrases over and over (echolalia)
- Gets upset by minor changes in routine or surroundings
- Has highly restricted interests
- Performs repetitive behaviors such as flapping, rocking or spinning
- Has unusual and often intense reactions to sounds, smells, tastes, textures, lights and/or colors
How much autism is “in the genes?”
One way to control for the effect of genes when doing research is to look at genetically homogeneous groups. A homogeneous group is a group that is all the same or similar. One of the best ways to being to understand what effects genes have and don’t have in certain diseases and disorders is to look at a homogenous group such as human twins.
Recent research in the Journal of the American Medical Association Psychiatry found that the genetic heritability of autism spectrum disorder is high compared with other factors. Heritability is the proportion of this total variation between individuals in a given population due to genetic variation. In this study, the researchers found that 56% to 95% of the effect is estimated to be genetic, according to a study of 258 twins. (Genetic influences on autism are estimated to be between 74-98% according to research by the Medical Research Council in the UK.)
This study used monozygotic and dizygotic twins. Monozygotic twins are identical twins. Dizygotic twins are fraternal twins. By using both types of twins, this allowed the researchers to study pairs of twins raised by their parents in the same household, which allowed researchers to look at prevalence rates of autism while also having pairs of twins exposed largely to the same environmental factors. According to the study, if one identical twin has autism spectrum disorder, the other twin has a 76 percent chance of also being diagnosed with it.
Researchers are aware that genetics are the primary drivers of autism. The issue is that they do not know which genes are. In this study, there were also significants effects from the environment in which the subjects were in, but the effects the environment had were about 1/2 to 2/3 as the genetic effect.
Another small study, published online in the International Journal of Epidemiology earlier in April in the journal International Journal of Epidemiology, found a possible association between the disorder and a father’s epigenetic tags, which help regulate genes’ activity. Doctors can detect epigenetic changes by testing sperm.
What goes on in the brain with Autism?
Autism is said to be one of the biggest mysteries in contemporary neuroscience. It is defined at the behavioral level, and its three hallmark features are known: impaired social interaction, communication difficulties and repetitive behaviors. What’s not clear, says Charles A. Nelson, PhD, is how autism arises and what the brain is like in someone diagnosed with autism, as compared with the typical brain. He and his colleagues are approaching these questions in a variety of ways.
Some of the greatest advances in autism biology have come from studying a handful of rare neurologic disorders that are caused by a single gene and sometimes include features of autism. Four of the best examples are Rett syndrome, Fragile X syndrome, tuberous sclerosis complex and Angelman syndrome. “It’s not that we think of these disorders as being part of autism,” Nelson explains. “It’s that a sizeable number of the kids with these syndromes wind up looking like they have autism.” Although there are different genes that are affected with each disorder, there is some common ground.
In Rett syndrome, which affects primarily girls & is often associated with autism, the affected gene makes MeCP2, which is a protein that dims the activity of many genes in nerve cells that influence synapse formation or function. The absence of MeCP2 causes dendrites, tree-like structures on neurons that receive incoming messages, to contain fewer spines, or spots for synapses to grow. The synapses that do develop do not function normally.
In Fragile X syndrome, associated with autism in at least a third of cases, the problem is somewhat the opposite. The affected gene makes FMRP, a protein that restricts the manufacture of many proteins at synapses. In its absence, dendrites grow wildly and contain more spines. But these spines are longer and thinner than normal, again, a sign of immaturity.
After diagnosis, how do you help children effected by autism learn?
This is my favorite part. Since 2013 I have worked at Hanover Elementary School in Meriden Connecticut where my mom is the principle, while I am home from school. At Hanover, they have a program called the STARS program where they completely change the learning curriculum to better fit their students with autism and various other conditions that may make it difficult for a student to learn in a typical elementary school environment. An example of this is incorporating a sensory room. This video perfectly explains what the STARS program is all about and how many little minds it has shaped and how many lives it has changed for the better. Spread the word about autism awareness today!