Pittsburgh – A number of theories have been formed by many researchers over the years in an attempt to identify the real reason behind Autism Spectrum Disorder (ASD). Scientists have already previously ruled out the theory that autism is caused by genes which were passed down to children from their parents– which leaves several other theories to consider.
While some studies implicate the increasingly polluted environment for the growing number of children with ASD, others attribute the developmental disorder to genetic mutations.
But scientists from Pittsburgh say that autism may have resulted from both.
Two recently published studies explained the genetic mechanisms that are likely to have played a huge role in the development of autism in children. Although a number of studies attribute ASD to spontaneous genetic mutations, according to researchers, these mutations are also likely caused by the harmful effects of a polluted environment.
A study by Kathryn Roeder of Carnegie Mellon University, along with Bernie Devlin of the University of Pittsburgh School of Medicine which was published in Nature Genetics back in July said that:
“most of the genetic risk for autism comes from versions of genes that are common in the population.”
Just last week, Roeder and her team published yet another study that reinforces their previous study.
Roeder and Devlin’s recently published study suggests that a total of 33 genes can be directly associated with ASD, with 74 others that researchers believe are also almost certainly associated with autism, too– a huge leap from previous theories by scientists that implicate only 9 of the human genes. Roeder told:
“Now we have 33 genes that we are certain of and 74 others that we are quite certain of. We are now investigating how these genes work together to build brain components, which presumably differ in autism.”
Based on large-scale statistical analysis done by researchers for the study, they found that an occurrence of a rare mutation in any of the identified genes can directly affect the formation of nerve networks in the human brain– which can severely impair cell communication.
According to Roeder,
“This makes sense because typical development of brain cells require intricate coordination of thousands of genes and appropriate communication between cells to ensure development of the brain — the most complicated organ in the human body.”
The study by Roeder and Devlin suggests that autism may occur when there is a new major variation in the genes, or when there is an accumulation of numerous common variants– or the occurrence of both. According to Devlin:
“This is all under the assumption that risk can act additively. But this seems to be a good approximation of reality.”
The original article by David Templeton in the Pittsburgh Post-Gazette can be found here
Contributed by Althea Estrella Violeta