About
Julie Steffann has been a member of the INSERM Unit “Mitochondrial Diseases” since 2006 and she focuses her research on mitochondrial DNA segregation during human embryo-fetal development. She is particularly interested in the diagnosis of genetic diseases caused by a mutation of mitochondrial DNA, and she developed and carried out the first prenatal and preimplantation diagnostics for mitochondrial DNA disorders. Her team is now a national and international leader in antenatal diagnosis in this field. They have shown that mtDNA mutant loads are stable in different cells of human preimplantation embryos and in different tissues of the human fetus (except the placenta), emphasizing the limitations of animal models in this field. Her studies also suggested that mtDNA can replicate in early embryos in order to obtain sufficient amount of wild-type mtDNA to sustain embryonic development in humans. Currently, her scientific work focuses on the characterization of the mechanisms that regulate the transmission of mitochondrial DNA molecules from a mother to her child, and the development of methods to prevent these diseases.
Scientific project
Julie Steffann's research focuses on the development and clinical translation of innovative genomic approaches for the diagnosis of rare genetic diseases, with a particular interest in the impact of impaired cellular energy metabolism on early human embryonic development. In this context, she investigates the consequences of mitochondrial diseases on preimplantation development and the interactions between the mitochondrial and nuclear genomes during human embryonic development, particularly in the context of mitochondrial replacement therapy. She also develops non-invasive prenatal diagnostic tools based on the analysis of circulating fetal DNA. As principal investigator, she has led several funded projects, including PRENATOME and PRENATSAFE, aimed at developing and evaluating novel non-invasive prenatal diagnostic approaches for monogenic disorders and assessing their clinical and health-economic impact. More recently, she has been developing long-read sequencing approaches to broaden access to preimplantation genetic testing and improve the diagnosis of complex genetic disorders.
2024Journal (source)J Exp Med