MicroRNAs (miRNAs) are a group of small RNA molecules which act as negative regulators of gene expression by controlling post-transcriptional regulation through binding to their corresponding mRNAs. Due to their small size, their nucleotide compositions are expected to be similar, but until now, the extent of similarity has not been reported in humans and their six phylogenetically closely related members of hominids. The present study allows direct comparison among six members of hominid species (Homosapiens, Gorillagorilla, Panpaniscus, Pongopygmaeus, Pantroglodytes and Symphalangussyndactylus) in terms of their miRNA repertoire, their evolutionary distance to human, as well as, the categorization of identical species-specific miRNAs. For this purpose, a total of 2694, 370, 157, 673, 590 and 10 mature miRNA sequences of Homosapiens, Gorillagorilla, Panpaniscus, Pongopygmaeus, Pantroglodytes and Symphalangussyndactylus respectively were retrieved from miRbase 22. A total of 12, 4, 4 and 3 conserved clusters with identical miRNA sequences that belong to the same gene families were found in Homosapiens, Gorillagorilla, Pongopygmaeus, Pantroglodytes respectively by neighbor-joining method using MEGA7 software. Interestingly, cross-species comparison has also shown a set of conserved identical miRNA sequences. Homologs of human mature miRNAs with 100% sequence identity are expected to have similar functions in the studied primates. Further in-vitro study is required to investigate common targets for identical miRNAs in the studied primates.
Deciphering conserved identical sequences of mature miRNAs among six members of great apes