1. Biological/Pharmacological Research Laboratories, Central Pharmaceutical Research Institute, Japan Tobacco Inc., Osaka 569-1125, Japan
2. Section on Genetics and Epidemiology, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA
3. Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
4. Laboratory of Animal Genetics, Division of Life and Food Sciences, Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan
5. Department of Laboratory Animal Science, Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan