While reviewing the source code of your CRISPRseek package I am confused about one thing. While examining the buildFeatureVectorForScoring function, I saw that it was written differently in the source code I downloaded and the R program. I'm confused as to which one is the latest version. I would be very grateful if you could explain why this difference. In BuildFeatureVectorForScoring2 function, the r.nucleotide [r.nucleotide == "T"] = "U" line failed when r.nucleotide contained "T". I think the reason is that the variable r.nucleotide in the previous line is perceived as a DNA sequence since it was created with DNAStringSet, and therefore does not contain "Uracil".