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The archaeological evidence suggests that Iran has been one of the first origins of sheep domestication in the world. This study aims to investigate the genetic diversity of indigenous Iranian sheep breeds using mitochondrial DNA (mtDNA) and to explore the evolutionary history of sheep domestication in Iran. Single Nucleotide Polymorphism (SNP) markers in the control region of mtDNA were used to genotype the unrelated sheep samples of Zel and Lori-Bakhtiari breeds which were collected from or near the center of the sheep domestication, using the Sequenom MassARRAY platform. Phylogenetic analysis of the mitochondrial SNPs classified all animals into either of two haplogroups A and B. The population differentiation (FST) and gene flow (Nm) statistics were 0.054 and 4.715 respectively, indicating a low mitochondrial genetic differentiation and high gene flow between two sheep breeds. The Analysis of Variation (AMOVA) showed that around 97% of the total genetic diversity is distributed within the two breeds. Further analysis using SNP haplotyping identified nine different haplotypes within the animals; eight haplotypes were present in the Zel, while only four were seen in the Lori-Bakhtiari breed. Two haplotypes, designated H1 and H3, were present at higher frequencies in both breeds. Haplotyes H5, H6, H7, H8 and H9 were found as population-specific in the Zel, and haplotype H2 only occurred in Lori-Bakhtiari breed. The existence of two common Haplotypes (H1 and H3) in the animals suggest that the two Iranian breeds from strikingly different geographical regions, may share a common ancestry, and these haplotypes could be the origin haplotypes while the population specific haplotypes developed later. [ABSTRACT FROM AUTHOR]

Introduction: We evaluated the performance of the new Abbott SARS-CoV-2 IgM assay on the Architect immunoassay analyser and compared it to the Architect IgG/Roche Cobas total antibody assays in both SARS-CoV-2 RT-PCR positive cases and healthy controls. Method: 200 healthy control samples and 48 individuals with other antibody-positive disorders (18 hepatitis/18 dengue/11 ANA/1 dsDNA) served to assess for potential cross-reactivity. Anonymised residual leftover sera positive for SARS-CoV-2 on RT-PCR were recruited as cases (N ​= ​133). The sensitivity/specificity/cross-reactivity of the Architect IgM assay were assessed. Concordance between the 3 assays were also analysed. Results: There was no cross-reactivity with controls and other antibody positive samples. The Architect IgM assay was 100% specific (95% CI 98.5 to 100) and sensitivity was 77.8% (95% CI 60.8 to 89.9) ≥14 days post-first positive RT-PCR (POS). Sensitivity of the combined Architect IgM and IgG results (30.8%) was significantly better than the Cobas total antibodies (15.4%) in early disease (p ​= ​0.04). While the Architect IgM assay had moderate agreement with the Cobas total antibody result (Cohen’s kappa 0.72), a combined Architect IgM and IgG result had better agreement (Cohen’s kappa 0.83). Conclusion: The Architect IgM assay has good specificity and no cross-reactivity with other antibody positive cases. A combined Architect IgM and IgG result has better sensitivity than the individual assays for early COVID-19. The Architect IgM assay is not comparable to the Cobas total antibody assay, but the Architect IgM and IgG combined result has good agreement with the Cobas assay.

Facial eczema ( FE) is a hepato-mycotoxicosis found mainly in New Zealand sheep and cattle. When genetics was found to be a factor in FE susceptibility, resistant and susceptible selection lines of Romney sheep were established to enable further investigations of this disease trait. Using the Illumina Ovine SNP50 BeadChip, we conducted a selection-sweep experiment on these FE genetic lines. Two analytical methods were used to detect selection signals, namely the Peddrift test (Dodds & McEwan, 1997) and fixation index FST (Weir & Hill, 2002). Of 50 975 single nucleotide polymorphism ( SNP) markers tested, there were three that showed highly significant allele frequency differences between the resistant and susceptible animals (Peddrift nominal P < 0.000001). These SNP loci are located on chromosomes OAR1, OAR11 and OAR12 that coincide precisely with the three highest genomic FST peaks. In addition, there are nine less significant Peddrift SNPs (nominal P ≤ 0.000009) on OAR6 ( n = 2), OAR9 ( n = 2), OAR12, OAR19 ( n = 2), OAR24 and OAR26. In smoothed FST (five- SNP moving average) plots, the five most prominent peaks are on OAR1, OAR6, OAR7, OAR13 and OAR19. Although these smoothed FST peaks do not coincide with the three most significant Peddrift SNP loci, two (on OAR6 and OAR19) overlap with the set of less significant Peddrift SNPs above. Of these 12 Peddrift SNPs and five smoothed FST regions, none is close to the FE candidate genes catalase and ABCG2; however, two on OAR1 and one on OAR13 fall within suggestive quantitative trait locus regions identified in a previous genome screen experiment. The present studies indicated that there are at least eight genomic regions that underwent a selection sweep in the FE lines. [ABSTRACT FROM AUTHOR]