Doctors at Johns Hopkins University (Maryland) analyzed more than 18,000 parent-child triads – children with autism and their parents – from different ethnic groups and created a new system for assessing the risk of developing this type of disorder, as follows from the results of a study published in Nature Genetics.
The new system, called PGS-TRI, allows clinicians to analyze scores using family data to determine the risk of autism spectrum disorder (ASD) and other neurodevelopmental disorders in offspring. This is done using the child's own DNA, genetic information from the parents and environmental factors, including the mother's diet and lifestyle.
First of all, the direct influence of inherited polygenic scores (PGS) is taken into account – that is, how much genetic factors influence the risk of developing a disease. The interaction of PGS with environmental factors is then analyzed – how environmental conditions can strengthen or weaken genetic predisposition. And then an error is added based on the indirect influence of parental data – how the genetic characteristics of parents, in addition to direct inheritance, can affect the health of the child.
Maternal genetic predisposition to obesity and neurocognitive disorders increases the risk of autism in children, experiments have shown, and general parental data allows us to estimate the indirect effects of genetic variations that affect offspring.
“The PGS-TRI method identified direct effects of genetic susceptibility markers for ASD and other neurocognitive traits due to genetic background, as well as asymmetric indirect effects of genetic susceptibility markers in parents,” the study states.
At the same time, the low accuracy of existing genetic tests for predicting the risk of developing the disease in representatives of non-European peoples indicates the need to collect and process more data from representatives of various population groups – scientists have identified this as the next step in research.
These gaps in information particularly affect people of African and Asian descent, so further research is needed to develop updated genetic tests for autism that can be used universally, Medical Xpress notes.
In an interview with the publication, senior study author Nilanjan Chatterjee, emeritus professor of biostatistics and genetic epidemiology at Johns Hopkins University, emphasized the innovation of this method.
“Concept [PGS-TRI] “has given us new insights into the complex relationship between genes and environment in developmental disorders such as autism, and has important implications for identifying risk factors and biomarkers using data collected from children, parents and their families,” Chatterjee said.
Nationally, about 1 in 31 children by age 8 are diagnosed with autism (3.2%), according to the U.S. Centers for Disease Control and Prevention (CDC). The diagnosis is 3 times more common in boys than in girls.
“Between 2009 and 2017, approximately 1 in 6 (17%) children aged 3 to 17 years were diagnosed with a developmental disorder. These include, but are not limited to, ASD, attention deficit hyperactivity disorder (ADHD), blindness, and cerebral palsy,” the CDC says.
