Table 1. OrbId summary. The full Ensembl³⁶ set of 178,375 unique human mRNA transcripts including 5′UTR, 3′UTR, and ORF annotations were compiled in and retrieved using the Biomart mining utility³⁷. “Human miRs analyzed” correspond to the full set of human miR mature sequences identified by Borchert et al. as originating from TEs²³ and were obtained from the miR Registry miRBase.².

Total human miRs analyzed	208
MiRs with predicted targets	191
Average # of predicted mRNA targets	7.9
Median # of mRNA targets	3
Max # of mRNA targets	94
Min # of mRNA targets	1
Total # of human transcripts assessed	178,375
Mean transcript length	1151 nt
Total # of 3’UTR targets	970
Mean 3’UTR length	386 nt
Total # of 5’UTR targets	410
Mean 5’UTR length	117 nt
Total # of ORF targets	149
Mean ORF length	647