The reality of pervasive transcription. by Clark, M, Amaral, P, Schlesinger, F, Dinger, M, Taft, R, Rinn, J, Ponting, C, Stadler, P, Morris, K, Morillon, A, Rozowsky, J, Gerstein, M, Wahlestedt, C, Hayashizaki, Y, Carninci, P, Gingeras, T, Mattick, J