Computational Biology, Graduate School of Humanities and Sciences, Center for Informational Biology, Ochanomizu University, 2-1-1 Otsuka, Bunkyo, Tokyo 112-8610, Japan. yura.kei@ocha.ac.jp|Computational Biology, Graduate School of Humanities and Sciences, Center for Informational Biology, Ochanomizu University, 2-1-1 Otsuka, Bunkyo, Tokyo 112-8610, Japan. yura.kei@ocha.ac.jp