People suffering from common and rare types of autism spectrum disorder could be exhibiting the same type of epigenetic modification in the brain, reports a recent study.
According to the study findings, more than 68 percent of patients with ASD, irrespective of the type of the disorder, have a similar pattern of histone acetylation. Histones are protein molecules wrapped in DNA. Acetylation is a histone modification in which an acetyl group is added to the end of a histone protein.
Factors Influencing Autism Spectrum Disorder
Shyam Prabhakar, the study's co-senior author at the Genome Institute of Singapore, said that epigenetic changes are seen in people suffering from any type of ASD. In spite of vast differences in heterogeneity and environmental factors that influence ASDs, they share one common factor, which is the molecular change in their epigenetic level.
The researcher added that the discovery could help in the development of a common drug for different types of ASDs. As it is well known that environmental and genetic factors play key roles in ASD, a number of researches dealt with mutations in the genome and variation in the DNA's protein coding.
Study On Autism Spectrum Disorder
However, it is noted in the current study published in the journal Cell that epigenetic changes — the changes that take place outside the DNA double helix — could be responsible for autism. While a number of prior studies focused on epigenetic modifications involving DNA methylation, they were far from establishing a link between epigenetic changes and psychiatric disorders.
Prabhakar and another co-senior author of the study, Daniel Geschwind from the David Geffen School of Medicine, analyzed the acetylation mark named H3K27ac because of its role in gene activation. Brain tissues from the temporal cortex, cerebellar cortex and prefrontal cortex of diseased ASD patients were used for epigenome analysis of H3K27ac alongside a control group of children aged 10 years and above.
Histone Acetylation Pattern In ASD Patients
It was found that more than 68 percent of the cases shared a similar histone acetylation pattern at 5,000 gene loci. The researchers also found a strong association between ASD and elevated levels of acetylation during the synapse formation and neuronal maturation at around 12 months of birth.
"This is the first large-scale study of how histone acetylation in the brain differs between disease and control samples, and part of a wave of new studies examining how the epigenome is perturbed in various diseases," Geschwind said.
The researchers also noted that further studies will be done to come up with a treatment option for ASD, which has no approved treatment by far.