[1] Univ Tsukuba, Inst Clin Med, Dept Internal Med, Tsukuba, Ibaraki 3058575, Japan
[2] St Marianna Univ, Sch Med, Inst Med Sci, Kawasaki, Kanagawa 216, Japan
[3] St Marianna Univ, Sch Med, Genet Program, Kawasaki, Kanagawa 216, Japan
[4] CREST, Chiba, Japan
[5] Chiba Univ, Sch Med, Ctr Biomed Sci, Chiba, Japan