NIEHS grant will support research on complex interplay of risk factors for autism
A University of Massachusetts Amherst epidemiologist has received a five-year, $3 million Outstanding New Environmental Scientist (ONES) grant from the National Institute of Environmental Health Sciences (NIEHS) in his ongoing effort to discover more about the origins and risk factors of autism.
The highly competitive NIEHS program, awarded just once a year to only a handful of young scientists, is designed to support innovative environmental health research by cultivating research leaders in the field early in their careers.
Youssef Oulhote, assistant professor in the School of Public Health and Health Sciences, will probe the interplay of early life exposure to environmental pollutants, the folate system during pregnancy and genetic susceptibility in the onset of autistic behaviors.
“We have multiple parts of the puzzle,” Oulhote says. “We want to put them together and add things that we don’t know yet.”
Oulhote will lead the project in collaboration with School of Public Health and Health Sciences colleagues Raji Balasubramanian, professor of biostatistics, and Anna Maria Siega-Riz, professor and dean. The research team also includes collaborators from Baylor College of Medicine, Brown University, Simon Fraser University in British Columbia, Canada, and Health Canada.
“This is a very prestigious award for Dr. Oulhote, reflecting the important contribution this research will make to the scientific field and his potential for being a leader in this field,” Siega-Riz says. “I am delighted to offer my expertise in nutritional epidemiology and am looking forward to working with him and the other investigators on this very important public health topic.”
To investigate several modifiable risk factors of autism in a comprehensive manner, Oulhote and colleagues will turn again to data from the Maternal-Infant Research on Environmental Chemicals (MIREC) prospective cohort study. MIREC enrolled 2,001 women during their first trimester of pregnancy from 10 cities in Canada between 2008 and 2011. The study already has resulted in more than 70 papers in scientific journals, including two led by Oulhote in Environmental Health Perspectives and Environment International.
Oulhote’s new research will build on the findings that exposure in the womb to phthalates – endocrine-disrupting chemicals found in common household products – was associated with autistic traits in young boys. But this link was not apparent in children whose mothers had taken the recommended dose of folic acid during the first trimester of their pregnancy.
“We want to look at other chemicals like air pollutants, especially ultra-fine particles, and pesticides, and also the constituents of those particles,” Oulhote says.
The research team will measure phthalates and organophosphate pesticides across two trimesters of pregnancy and estimate monthly exposures to individual air pollutants, such as nitrogen dioxide and particulate matter and its composition, across pregnancy and during the child’s first year.
They will also look at folate levels in maternal blood samples, as well as folate receptor autoantibodies. “It appears that the mothers of kids with autism have a higher prevalence of folate receptor autoantibodies that interfere with folate metabolism and transport. So even if they have enough folate intake, it may not be transported properly to the brain,” Oulhote explains.
The use of sophisticated statistical models will help researchers understand the intricacies and interplay and impact of various risk factors. “We’re applying and adapting newly developed machine learning methods because we know we have a complex problem,” Oulhote says. “You can’t just look at everything separately – we want to take a holistic view and have methods that can take into account this complexity.”
Oulhote hopes the research will lead to better prevention strategies for autism spectrum disorder and its associated behaviors at both the individual and population levels.
“We want to gain a better understanding of how strongly multiple pollutants and the folate system are associated with autistic traits, whether these chemicals are associated with circulating folate concentrations, and how these effects of multiple pollutants differ based on folic acid intake, genetic susceptibility and the presence folate autoantibodies,” he says.