A given tRNA does not yield tRF-5, -3 and -1 at equal abundance. (A) Number of reads per million of tRF-5s, tRF-3s and tRF-1s from selected tRNA genes. The tRNA genes were selected on the basis of tRF-1s that had >20 reads per million in HEK293 human cell line library. The tRF-1s were compared with tRF-5s and -3s from the same tRNA, regardless of whether the tRF-5 or -3 was derived from that specific tRNA gene or other members of the tRNA gene family. The duplicated tRNA genes (tRNAs with the same anticodon) are marked with special character "*", "#", "$", "%" and &. (B) Scatter plots of tRF-3s versus tRF-5s, tRF-1s versus tRF-3s, and tRF-1s versus tRF-5s for the tRNA genes shown in A along with Pearson correlation coefficients.