Autism Spectrum Disease (ASD), which is also commonly known by the term “spectrum“, refers to those who have mild social impairments, intellectual disabilities, or epilepsy.
Although genetic studies offer some clues about ASD, it was a major success that genes linked to ASD were discovered. Scientists are still trying to figure out how they all fit together and what causes so many ASD symptoms.
Nature Genetics magazine published the following study in its online edition, on June 2nd, 2022. A group of scientists from all parts of the world, led by researchers from the University of California San Diego School of Medicine (UCSD), reported significant progress on understanding genetic variation and rare mutations which affect the likelihood of ASD development in children.
Jonathan Sebat Ph.D. (senior research author) is a professor at the Beyster Center for Molecular Genomics of Neuropsychiatric Diseases.
Sebat’s group analyzed the genomes of 37.375 individuals, based on 11213 ASD-related family members. This study was performed to find out how genetic factors may influence clinical symptoms or risk.
Researchers considered many factors. These include de novo varieties, which can only be found in new-borns, and polygenic scores. These measures can be used to measure the genetic effects of common variants.
Sebat said, “When you combine the main factors that are detectable in a genome DNA,” “the predictive accuracy for DNA sequencing more over doubles when you only test one category at once.” Genetic testing could become more precise by combining rare genetic mutations with multigenic scores.
The risk of autism is also affected by your gender. ASD is more common among males than in females (4 to 1) The study’s authors discovered that ASD prevalence is lower in females than it is in males. This could be due to a “female protection effect,” in which females are less susceptible to genetic risk.
They found that the total genetic burden of ASD children and their siblings was higher for females than for males.
Sebat explained that both rare variants, as well as polygenic scores, show evidence of a female protective function’. “This suggests the autism liability threshold differs by sex, with females having higher thresholds than males.”
Sebat stated that ASD symptoms can vary in severity due to genetic risk. “People with autism may be on the extreme end of the spectrum, but there are many risk factors for everyone.
The authors also discovered different gene expressions for different genetic elements in the developing brain.
Very rare variants in genes were abundant in neurons of fetal brains. This may account for some of the correlations between brain expression and other traits.
Researchers concluded that autism spectrum disorders can be explained by individuals with their own genetic makeup.