An Edinburgh native, Mirren gained a BSc (Hons) in Genetics from the University of Glasgow in 2014. An MSc in Science Communication and Public Engagement from the University of Edinburgh followed in 2015, after which she worked in the sector for the next three years. Having always been interested in the practical applications of biology, she undertook an MSc in Synthetic Biology and Biotechnology at Edinburgh, graduating with Distinction in 2019. As part of the MSc, she took part in the 2019 iGEM competition, working on azo dye detection and bioremediation, for which the team was awarded a Silver Medal. She joined the lab in 2020 as a research assistant working on metabolic engineering of bacteria to produce high-value products, before joining the IBioICPhD programme in October 2020 to work on the sustainable production of industrial chemicals using a combination of engineered bacterial metabolism and chemical catalysis in collaboration with MiAlgae. Mirren passed her viva in April 2025 and have stayed with the Wallace lab as a PDRA.