He received MSc (1986) and PhD (1991) degrees from the University of Kuopio, Finland studying the molecular bases of a lysosomal storage disease, aspartylglucosaminuria. He then began a postdoctoral fellowship at Childrens Hospital Los Angeles with Dr. John Groffen and Dr. Nora Heisterkamp, where he specialized in developmental biology with particular emphasis in mouse genetics and organogenesis. In 1997, he joined the faculty of the University of Southern California, and the Developmental Biology Program in the Saban Research Institute. In 2008, he joined the faculty of University of Michigan. His research program focuses on growth factor signaling in craniofacial and cardiac development. Dr. Kaartinen has served in several institutional and national committees including both NIH and American Heart Association grant review panels, and he is a reviewer for many scientific journals.