Dear all, I have the impression that the function oligonucleotideTransitions from the Biostrings package (version 2.9) has an unexpected behavior, it only analyzes the first sequence of the DNAStringSet variable used as input. Looking to the code of this function, I have the impression that it is just because it is using the function oligonucleotideFrequency without the parameter simplify.as set to value "collapse". Probably this parameter was added to the function oligonucleotideFrequency later than when oligonucleotideTransitions function was implemented. This is an example of what I call an unexpected behavior (I just set the parameter left=0 to simplify the result): > seq<-DNAStringSet(c("AAAAA","TTTTT")) > oligonucleotideTransitions(seq,left=0) [,1] [,2] [,3] [,4] [1,] 5 0 0 0 when the result should be [,1] [,2] [,3] [,4] [1,] 5 0 0 5 Should forward this message to the maintainer of the Biostring package? Which is his email? Thanks, Jose Dr. Jose M Muino Plant Research International B.V. Droevendaalsesteeg 1 P.O. Box 16, 6700 AA Wageningen, The Netherlands Phone: +0317-481122. E-mail: jose.muino at wur.nl http://www.pri.wur.nl