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The interferon regulatory factor gene family encodes transcription factors with multiple biological functions, which include reproduction, cell differentiation and immunity. Interferon regulatory factor-5 (IRF-5) gene is involved in immune defence against virus, stress response, activation of type I interferon genes, cell differentiation and growth. This experiment was conducted to identify and characterise single nucleotide polymorphisms in exons 3, 4, 5 and 7 of IRF-5 gene in Nigerian local chickens. Exons 3, 4, 5 and 7 of IRF-5 gene were amplified and sequenced. Single nucleotide polymorphisms (SNPs) present in exons 3, 4, 5 and 7 of IRF-5 gene were identified and analysed using Clustal W, DnaSp and SNAP2 software packages. Four SNPs, rs317511101, rs312902332, rs315149141 and rs739389464, were identified in exon 3 of IRF-5 gene in all the three genotypes. Exon 4 of the gene was conserved while three of the SNPs (rs736423928, 170C>T and rs740736761) identified in exon 7 were shared among the three genotypes. Linkage disequilibrium of 1.00 existed between rs317511101 and rs315149141 polymorphisms identified in exon 3 of normal feathered and frizzle feathered chickens. Mutation rs740736761 identified in exon 7 had the highest polymorphism information content obtainable for any biallelic marker. Most of the SNPs identified in exons 3, 5 and 7 were synonymous and singletons which could not be used for association study. The study concluded that only haplotypes in exons 3 and 7 of IRF-5 gene can be used in marker-assisted selection when improving Nigerian local chickens.

The aim of the study was to determine the clinical relevance of cyclin D1 (cD1) and its association with clinicopathological parameters in breast cancer patients treated with hormonal therapy. Material and methods The study included 96 primary breast cancer patients with known clinicopathological parameters. In adjuvant setting, 44 patients were tamoxifen-treated and 52 were treated with ovarian irradiation/ablation. The cD1 status (gene amplified/nonamplified) was determined on formalin-fixed paraffin-embedded tumor tissue sections by chromogenic in situ hybridization. Associations between parameters were analyzed by Chi-square and Spearman’s rank order correlation tests. Cox proportional hazards regression test was performed. Survival curves for relapse-free survival were constructed according to the Kaplan-Meier method. Results There were no significant associations between cyclin D1 and clinicopathological parameters in either patient group. Amplified cyclin D1 associated significantly with the actual relapse incidence in the ovarian ablation patient group (p = 0.01, HR = 3.1), but not in the tamoxifen-treated patient group. Estrogen receptor and cyclin D1 have proven to be independent parameters of poor outcome in the ovarian ablation patient group (p = 0.03, HR = 2.9; and p = 0.009, HR = 2.5; respectively). Conclusions Cyclin D1 might be a candidate biomarker of poor outcome in breast cancer patients treated with ovarian ablation, suggesting its possible involvement in acquirement of hormonal resistance. The role of cyclin D1 as potential parameter of response to tamoxifen was not as pronounced.

Understanding the level of genetic diversity in any population is an important requisite towards strategizing measures for conservation and improvement of stocks. This study focused on the assessment of phylogenetics and molecular divergence of tilapia fish species obtained from two populations (Domita in South-South and Odeda in South-West, Nigeria) using the displacement loop (D-loop) and cytochrome b region of the mitochondrial deoxyribonucleic acid (mtDNA). A total of 28 samples (15 from South-South and 13 from South-West) were used for the genetic analysis. DNA was extracted from the tissue of all the samples using Quik-gDNATM miniPrep kit. The D-loop containing the hypervariable region was sequenced for all samples from the two populations, while cytochrome b (Cyt b) region of mtDNA was only sequenced for samples from South-South population. Chromatograms of the sequences were viewed and edited using Bioedit software. Multiple sequence alignment was carried out using molecular evolutionary genetic analysis (MEGA) software before subsequent genetic analyses. Phylogenetic analysis grouped the samples into two clusters based on population. Also, when the two mitochondrial regions were pooled together, they clustered into two major groups based on mitochondrial regions. Analysis of molecular variance (AMOVA) revealed 37.32% variation within population and 62.68% variation among population with a significant fixation index of 0.627 (p < 0.05). The genetic distance inferred between D-loop regions of South-South and South-West populations was 0.243. Maternal lineage analysis revealed that the origin of tilapia fish from both populations could be traced to Oreochromis spirilus and Oreochromis leucostictus based on mitochondrial D-loop region. The findings of this study revealed molecular divergence among the tilapia populations and may serve as pivot information for the genetic improvement of this important species.

Aim: The aims are to study the genetic diversity and population structure of Tilapia fish species in Nigeria using mtDNA D-loop region and time divergence of these various groups of fish to give a baseline information for fish management and conservation programs. Methodology: Blood samples from four species of tilapia were collected with the use of FTA cards for DNA extraction and PCR amplification. A 941bp long fragment, including the D-loop, was subsequently used for analysis. Molecular diversity indices and Tajima’s selective test were determined. A phylogenetic tree was constructed for all the four fish species using UPGMA. The divergence time among the four fish species using MEGA5 software.

In this study, the maternal genetic diversity, phylogenetic relationship and effect of natural selection on indigenous chickens from Nigeria were assessed. A total of 397-bp fragment of the mitochondrial DNA (mtDNA) D-loop region of 171 indigenous chickens from four populations of Nigeria and four commercial egg line strains (two Anak titan, one Giriraja and one Yaffa) as out-groups were analysed. Thirty-one haplotypes (28 from Nigerian chickens and three from commercial strains) and 34 polymorphic sites were identified. The mean haplotypic and nucleotide diversity were found to be 0.39 ± 0.05 and 0.02 ± 0.02, respectively. Majority of Nigerian chicken haplotypes observed were grouped into haplogroup D which originated from Indian subcontinent, suggesting a single maternal lineage. Genetic variation within and between populations accounted for 97.30 and 2.70% of the total genetic variation, respectively, which is in agreement with a recent and maternal founding effect. High number (4) of negatively selected sites observed based on single likelihood ancestral counting (SLAC) model indicated that the sampled Nigerian chicken populations were undergoing purifying selection. This study concluded that there was relatively high genetic diversity and differentiation, thus, this information will probably paveway for further evaluation studies, preservation and improvement of Nigerian chickens as genetic resources towards ensuring food security.

Mitochondrial DNA (mtDNA) hypervariable region 1 ( HV1) sequences of three Nigerian indigenous goat breeds; West African Dwarf (WAD), Red Sokoto (RS) and Sahel were used to investigate the genetic diversity and effect of selection between and among these populations. Deoxyribonucleic acid (DNA) of Nigerian indigenous chicken was extracted from blood samples collected and preserved on Fast Technology for Analysis (FTA) paper. The extracted DNA were amplified and sequenced with predefined mitochondria (mtDNA) primer sets for HV1. Eighty-seven (87) polymorphic sites were found in 115 sequences which were grouped into 92 haplotypes. The mean haplotypic and nucleotide diversity were found to be 0.996±0.002 and 0.092±0.04 respectively. Genetic variation within population and between populations accounted for 97.26% and 2.74% of the total maternal variation respectively, with FST value of 0.0274. The Tajima's (D) and Fu's (F) test of neutrality were significant (P