Professor Justin St. John was awarded his PhD in 1999. In 2000, he was awarded a Mellon Fellowship at the Oregon National Primate Research Center, Oregon, USA. His achievements as an early career scientist led to his rapid promotion to the position of Professor at the University of Warwick (2007). Whilst in the UK, he was funded by the Medical Research Council and received an Endeavour Fellowship to undertake a period of research at Monash Institute of Medical Research where he has been Director of the Centre for Reproduction and Development and a Professor in the Faculty of Nursing, Medicine and Health Sciences at Monash University since November 2009. His research focuses on developing and using specific model systems to understand how mitochondrial DNA is transmitted and replicated. He was the first to demonstrate that sperm mitochondrial DNA could persist in the late stage embryo and thus be transmitted; describe mitochondrial DNA replication events in undifferentiated and differentiating embryonic stem cells; and demonstrate why donor cell mitochondrial DNA is transmitted to embryos and offspring following somatic cell nuclear transfer. He is using these outcomes to develop mini-pig models of mitochondrial DNA disease and reproductive strategies to prevent the transmission of mutant mitochondrial DNA from one generation to the next. He has published in The Lancet, Nature Chemical Biology, Nature Cell Biology, Stem Cells, Journal of Cell Science, and Genetics.