Autism: Causes and How to Help
Written by Laurel Geraci
Edited by Priya Ram
Jan 31, 2021
Edited by Priya Ram
Jan 31, 2021
With the recent arguments presented by the anti-vaccination communities, talks about autism and its origins have been appearing more frequently in mainstream media. There is no scientific evidence or correlation to suggest that vaccines cause autism and medical professionals are still unsure of just how many genes contribute to an autism diagnosis. Looking at studies of identical twins show that autism spectrum disorders (ASDs) have an extremely high heritability, estimated at about 90%,yet we struggle to pinpoint what genes are responsible for ASDs. The answer is not quite simple.
In high school biology classes, most students learn about the principles of a Punnett Square: if a mother has genotype Aa and a father has genotype Aa, then their child will have a 25% chance of having AA, a 50% chance of having Aa, and a 25% chance of having aa. Unfortunately, disorders like autism don’t follow this pattern of Mendelian inheritance, and the etiology of ASDs is widely debated. One proposed hypothesis suggests that defects in neuron communication are what cause the abnormal physical behaviors associated with ASDs, such as stimming (repetitive sounds and actions in response to intense emotions) or tantrums caused by overstimulation. Neuron communication is essential for the production of the feel-good hormone serotonin, and biochemical studies show that genes related to serotonin are the ones most commonly affected by ASDs.
Random and/or rare mutations in specific genes might also be responsible for ASDs, and these genes are later passed down onto the next generation. However, the difficulty of exploring this hypothesis is that with spontaneous mutations, it is nearly impossible to track correlations or causations. ASDs appear much more commonly in males compared to females with a ratio of about 4:1, which gave researchers a reason to believe ASDs might be partially determined by the X chromosomes. Some of these theories are consistent with behaviors observed in mice with mutations in these candidate genes, but unfortunately the majority of these genes have inconclusive results.
Overall, it seems that whatever genes are responsible for autism spectrum disorders all control biological tracks essential to neurotransmission. While scientists are certain ASD’s are indeed heritable, no single gene’s mutation can be pinpointed across all observed patients with autism. Because of this wide array of genomes, there are no approved treatments prescribed to work for all autistic patients. Depending on the most detrimental symptoms, patients can be given antidepressants, antipsychotics, or even stimulants to help. However, these drugs are typically not approved for adolescent usage. But be aware that autism spectrum disorders are not a death sentence, and that early behavioral practices and support will greatly improve the trajectory of the patient’s condition. If this concern presents itself, talk to a pediatrician about a personalized psychopharmacological intervention plan for your child that can help correct these biological pathways. Your understanding and proactive attitude towards their disorder early on will be greatly appreciated and remembered for the rest of their life.
Works Cited
Dexter Hadley, MD. "Genetics of Autism Spectrum Disorders: Background, Genetic Etiology,
Clinical Implications of Genetic Changes." Genetics of Autism Spectrum Disorders:
Background, Genetic Etiology, Clinical Implications of Genetic Changes. Medscape, 09
Nov. 2019. Web.
Image Source: “Puzzle Heart Pendant by MICHE MOZAIX” by Deborah Cooper-Asberry licensed under CC BY-NC 2.0