Solute carrier family 11 member a1 gene (Slc11a1) previously known as natural resistance-associated macrophage protein 1 (Nramp1) is a gene of member of family of metal ion-transport protein. The cellular expression is restricted to phagocytic cells. Slc11a1 delivers bivalent metal cations from the cytosol into acidic endosomal and lysosomal compartments where Fenon and Haber-Weiss reaction generates toxic antimicrobial radicals for direct antimicrobial activity against harmful microorganisms. The present study was undertaken with the objective of analyzing Slc11a1 gene to gain insight into the evolutionary proximity and divergence as well as the polymorphism of this gene in ruminants and non-ruminants including the attendant effects of the genetic variants on the function of the Slc11a1 protein. Thirty Slc11a1 gene sequences of 6 mammalian species classified as ruminant (goat, sheep, cattle, Bubalus bubalis and Bubalus carabanensis) and non-ruminant (swine and horse) animals were investigated. The length of the Slc11a1 gene varied from 448-2,357. There was substantial genetic variation and polymorphism in the aligned sequences of Slc11a1 gene within and across species. Functional analysis of non-synonymous mutations in cattle revealed that twenty five of the amino acid substitutions at the peptide binding region could be beneficial, (E36G), (T52A), (N161S) and (V248I) were likely to be beneficial while only (Q312K) was harmful. In horse, two of the amino acid mutations were harmful, two were likely to be harmful, one was undecided, four were likely beneficial and the rest twenty were beneficial. The phylogenetic trees showed some form of proximity and differentiation in Slc11a1 sequences within and across species. The present information on the polymorphism of Slc11a1 gene might be exploited in the search for association with disease resistance in Nigerian livestock species.

MicroRNAs (miRNAs) are small endogenously expressed single-stranded RNAs that regulate gene expression post transcriptionally and shape diverse cellular pathways. miRNAs regulate a wide range of biological processes through the recognition of complementary sequences between miRNAs and their target genes. The present investigation aimed at determining in-silico the genetic variability of miRNA genes in some livestock and non-livestock species. Effects of single nucleotide polymorphisms (SNPs) in genes? 3'UTR on target gain/loss of human miRNAs were also explored. A total of twenty four mature miRNA sequences and genomic coordinates in three livestock [chicken (5), pig (1) and cattle (9)] and two non-livestock (human (6) and mouse (3)] species were retrieved from the miRBase 15 release. Computational scanning of polymorphisms in the miRNAs revealed 33 and 20 polymorphic sites in livestock and non-livestock species, respectively. Of this, 7 (chicken), 11 (cattle) and 2 (mouse) were located within the seed region. The de novo computational prediction revealed that SNPs rs1042725 (C/U) and rs1044129 (A/G) in genes? 3'UTR of human miRNAs positively influenced the target site thereby resulting in target gain. However, the effects of SNPs rs56109847 (A/G), rs28927680, rs12720208 (G/A) and rs5186 (A/C) were negative. The evolutionary tree showed that the relationship between miRNA consensus sequences of livestock (pig, chicken and cattle) was closer compared to non-livestock species (mouse and human), which could be implicated in morphological complexity among vertebrates. Although the function of miRNA is only beginning to be understood, future in-silico research evaluating the functional effect of miRNA in gene translation and subsequent biological pathways especially in livestock is of paramount importance; and this should be complemented with hypothesis-driven experimental studies to evaluate the phenotypic effect of identified miRNA genetic polymorphisms in animals.