Fertility expert Mary Herbert and her team are preventing the transmission of mitochondrial DNA disease using nuclear transplantation. This cutting edge mechanism, commonly referred to as three-person IVF, has the potential to prevent transmission of devastating disease from mother to child. Mary’s work has also been critical in the development of a UK law change that permits these new techniques to be offered in clinical treatment. In addition to mitochondrial disease, Mary’s research focuses on the underlying causes of infertility, miscarriage and birth defects in older women. She is a Fellow of the Royal College of Pathologists and a member of the scientific advisory board for the Association of Clinical Embryologists in the UK. Mary is currently a Professor of Reproductive Biology at Newcastle University, and Scientific Director at Newcastle Fertility Centre.