Researchers at Danish Project iPSYCH & the Broad Institute in USA have found a common genetic risk for autism. The discovery means the determination of genes by separating the diagnosis groups and making more exact diagnoses will be accessible in the future.
Autism is a neurological development disorder with highly variable features. Autism spectrum bdisorders are estimated to affect about one percent of the population. During recent years, researchers have tried to explain the cause of autism & the essential role of them. Finally, by international collaborations, the first common genetic risk variants for autism and the genetic differences between types of autism has been detected.
“Despite many years working, recognizing exactly which genes are involved has been very challenging,” says Professor Mark Daly from Broad Institute. In this study, five genetic variants increasing the risk of autism, have been reported by comparing the genomes of 20,415 people living with autism. Furthermore, when combining the dataset with genetic data from related mental disorders, another seven gene variants were identified which have been recently published in the scientific journal Nature Genetics.
“Based on the study, we have examined all the approximately 9 million frequent variants that can be found in the genomes of the people who are included in our study. These are genetic variants which are common in the population at large and where the individual variant’s contribution to the risk is very small,” explains Associate Professor Jakob Grove from Aarhus University.
“By comparing the genetic risk variants with the genes’ expression and the 3-D structure of the genome in the developing brain, we can show that the identified risk genes are important for the development of the brain, and in particular, the development of the cerebral cortex,” explains Professor Anders Børglum from Aarhus University.
A significant overlap between the genetic background for autism and other mental disorders such as schizophrenia and depression have detected by the researchers. “The positive correlation with educational attainment might seem paradoxical, because some autistic people have reduced cognitive function, and on average, fewer people with an autism diagnosis end up with a higher education. The correlation is seen in several previous studies, and in our data we can confirm that in general, this correlation between the genes for autism and genes that predispose for longer education does exist,” says Jakob Grove. “However, we can demonstrate that it does not apply to all subsets of autism.”
Autism refers to a very mixed group with different autism disorders. Some have very pervasive developmental disorders with mental retardation, while others may be cognitively well-functioning with a normal or high IQ.“We can for the first time establish genetic differences between the various diagnostic subgroups. This indicates that larger studies in the future will be able to pinpoint genes that separate the diagnostic groups and enable more precise diagnosis and advice for the individual person suffering from an autism disorder.” says Anders Børglum.FEBRUARY 27, 2019 By Aarhus University Resource: medicalxpress.com