Affiliation: | a Division of Stem Cell Biology, Medical Research Center, MizMedi Hospital, 701-4 Naebalsandong, Kangseogu, Seoul 157-280, South Korea b Department of Life Science, College of Natural Sciences, Hanyang University, South Korea c Developmental Genetics, School of Biological Sciences, Seoul National University, South Korea d Division of Biotechnology and Genetic Engineering, College of Life and Environmental Science, Korea University, South Korea |