For the study, the research team wanted to determine not just when genes activate, but how their activation changes over the course of brain development. Genes activate at different points in cell development, but mapping gene development has been difficult. And past studies have focused on isolated moments in time, not on how gene expression evolves over time. Researchers then developed an AI model to predict gene expression over time based on changes in nearby chromatin. “Our equation will tell you exactly the switching point — or the point of no return after which the drug will not have the same effect on the gene’s expression,” Borsari said.