Project description:We used deep sequencing to characterize 3 families of sRNAs (piRNAs, miRNAs, and tRFs) present in Sus scrofa gonads and focused on the sRNA fraction present in both male and female gonads. Of the sequences detected in the testes, 2.6% of piRNAs, 9% of miRNAs, and 10% of tRFs were also present in the ovaries. Notably, the majority of the shared piRNAs mapped to the introns of ribosomal RNAs and were derived from clustered loci. In addition, the most abundant miRNAs present in the ovaries and testes are conserved and are involved in many biological processes such as the regulation of homeobox genes, the control of cell proliferation, and carcinogenesis. Unexpectedly, we detected a novel sRNA type, the tRFs, which are 30–36-nt RNA fragments derived from tRNA molecules, in gonads