Blocking of targeted microRNAs from next-generation sequencing libraries

Highly abundant microRNAs (miRNAs) in small RNA sequencing libraries make it difficult to ob-tain efficient measurements of more lowly expressed species. We present a new method that allows for the selective blocking of specific, abundant miR-NAs during preparation of sequencing libraries. This technique is specific with little off-target effects and has no impact on the reproducibility of the measure-ment of non-targeted species. In human plasma sam-ples, we demonstrate that blocking of highly abun-dant hsa-miR-16–5p leads to improved detection of lowly expressed miRNAs and more precise measure-ment of differential expression overall. Furthermore, we establish the ability to target a second abundant miRNA and to multiplex the blocking of two miR-NAs simultaneously. For small RNA sequencing, this technique could fill a similar role as do ribosomal or globin removal technologies in messenger RNA sequencing