Summer Thyme, PhD
Summer Thyme, PhD, assistant professor of biochemistry & molecular biotechnology, is the recipient of a five-year, $4.1 million National Institutes of Health grant under the Transformative Research Award for the INCLUDE (Investigation of Co-occurring Conditions across the Lifespan to Understand Down syndrome) Project to study intellectual disability in neurodevelopmental disorders using zebra fish as the model organism.
With the grant, Dr. Thyme will study genes related to Down syndrome, with the aim of providing a foundation for understanding its causes and addressing the need for new treatments for intellectual disability. Thyme’s lab will investigate disrupted mechanisms of brain development and screen for small molecules that can prevent observed abnormalities.
“Intellectual disability is one of the biggest issues and challenges in neurodevelopmental disorders. Almost no research has been done on Down syndrome using zebra fish. It’s a big research gap, but Down syndrome is the most common genetic cause of intellectual disability,” Thyme said.
Thyme has done similar research with zebra fish, studying schizophrenia, autism and other psychiatric disorders. She highlighted the potential of zebra fish models for drug screening, as well as identifying genetic factors that impact learning in humans.
“Zebra fish provide a nice balance between gene conservation and throughput so you can test a lot of genes or molecules with them. Zebra fish are vertebrates with similar brain structure and molecular pathways as ours. You shouldn’t assume that their behavior will be identical to humans, but we plan to see if the genes that impact learning in humans also impact fish behavior,” she said.
Thyme credits the work of Anna Moyer, PhD, a postdoctoral researcher who joined the Thyme lab in 2022, as a major contributor to their research in Down syndrome. Dr. Moyer is exploring how misexpression of chromatin regulators (which control how DNA is packaged within cells) affects a signaling pathway called Sonic hedgehog that regulates embryonic morphogenesis—the differentiation of cells, organs and tissues—in animals.
Their research hypothesizes that during a human’s embryonic stages, the increased number of genes present on the triplicated human chromosome (for Down syndrome, chromosome 21) causes a reduced response in hedgehog signaling. By identifying the genes that contribute to signaling defects, they hope to reveal the underlying causes of Down syndrome.
Thyme and Moyer will also be screening FDA-approved drugs and other products as possible new treatments for intellectual disability in Down syndrome. No approved drug treatment exists for intellectual disability.
Thyme joined UMass Chan in 2023 after spending four years as an assistant professor of neurobiology at the University of Alabama at Birmingham Heersink School of Medicine. She earned her PhD in biochemistry from the University of Washington.
