Janet Rossant

Janet Rossant
Born	(1950-07-13) July 13, 1950
Occupation(s)	Developmental biologist, stem cell researcher, professor
Years active	1976–present
Known for	Research on gene function during embryogenesis, identification of trophoblast stem cells

Janet Rossant (born 13 July 1950) is a developmental biologist acclaimed for her groundbreaking investigations into gene functions during embryogenesis. A prominent figure in developmental biology, her studies concentrate on stem cells, molecular genetics, and the genetic regulation of early mouse embryo development. Rossant’s research has provided significant understanding of embryonic growth processes, stem cell formation, and gene regulatory pathways. In 1998, her contributions were instrumental in identifying the trophoblast stem cell, which enhanced knowledge regarding congenital defects affecting the heart, vasculature, and placenta.

She holds the positions of President and Scientific Director at the Gairdner Foundation, is a senior scientist within the Developmental & Stem Cell Biology Program, serves as chief of research at Toronto’s Hospital for Sick Children (SickKids) Research Institute, and is a professor at the University of Toronto in Molecular Genetics, Obstetrics/Gynecology, and Pediatrics. Additionally, Rossant acts as deputy scientific director for the Canadian Stem Cell Network and is a senior editor for the journal eLife. In 2013, she presided over the International Society for Stem Cell Research.

Education

Janet Rossant completed her Bachelor of Arts with First-Class Honors in zoology at the University of Oxford in 1972. She then earned a PhD in mammalian development from Darwin College, University of Cambridge in 1976.

Sick Kids Lab

At SickKids in Toronto, Rossant’s laboratory concentrates on stem cell and embryonic biology by investigating early mouse embryo cell fate decisions to better comprehend how embryo-derived stem cells are maintained and differentiated. This expertise is applied to convert human induced pluripotent stem (iPS) cells into various cell types to study human biology and disease mechanisms. The lab employs techniques such as genetic engineering, live-cell imaging, proteomics, and single-cell transcriptomics.

Awards

Rossant has been honored with numerous distinguished awards recognizing her impact on developmental biology and stem cell science. In 2015, she received the Canada Gairdner Wightman Award for her advances in understanding human genome function, congenital disorders, and cancer therapeutics. Her pioneering work with mouse genome manipulation has firmly established this model organism as essential for studying human genomic functions.

In 2013, she was awarded the Ross Harrison Prize by the International Society of Developmental Biologists for her lifetime achievements in developmental biology. This accolade acknowledged her contributions to clarifying human embryogenesis and developing targeted gene mutation techniques in mouse embryos.

A dedicated advocate for women in STEM fields, Rossant was among five laureates honored with the 2018 L'Oréal-UNESCO For Women in Science Awards, which aim to encourage girls worldwide to pursue careers in science, technology, engineering, and medicine.

Selected publications

Additional publications can be accessed via PubMed.

Embryonic Research

Rossant’s investigations into cellular reprogramming have led to the development of critical proteomic resources for stem cells and introduced novel approaches to study mechanisms governing cell fate determination. Her lab identified specific cell surface markers that enable monitoring differentiation across embryonic (ES), epiblast (EpiSC), trophoblast (TS), and extraembryonic endoderm (XEN) stem cell populations.

Stem Cell Research

One of Rossant’s landmark achievements was the 1998 identification of trophoblast stem cells. This discovery allowed for stable isolation of trophoblast lineages through fibroblast growth factor 4 (FGF4) treatment applied to mouse blastocysts or early postimplantation trophoblast tissues—lineages critical for mammalian embryo viability during gestation.

Her work on pluripotent stem cells further advanced protocols for generating lung epithelial tissue in mice, offering promising avenues for regenerative medicine and therapeutic strategies targeting pulmonary diseases. These findings deepen comprehension of pluripotent stem cell capabilities and their potential clinical applications in lung disorder treatments.