This review explores the usefulness retinoic acid (RA) related physiological factors as
possible biomarkers of embryotoxicity. RA is involved in the morphogenesis of the early
embryo as well as in the development and maturation of a wide variety of organ anlagen.
The region-specific homeostasis of RA in the embryo is in many ways the driving force
determining developmental cell proliferation versus differentiation. As a consequence, RA
concentrations are carefully controlled in time and space in the developing embryo. RA …