design: Six sterile paper points were taken as a mock sample. RNA and DNA were simultaneously isolated from each sample using a custom protocol. After rRNA depletion, transcriptomic libraries were prepared using the ScriptSeq v2 RNA-Seq Kit (Illumina). Sequencing was performed in single-end mode, producing reads of 50 or 68 base pairs, on an Illumina HiSeq 2500 sequencer with the TruSeq SBS Kit v3HS (Illumina). BCL files from RNAseq were converted into FASTQ files (single-end reads) using the bcl2fastq software version v2.20.0.422 (Illumina).