Detection of hybrids between wild boars (Sus scrofa scrofa) and domestic pigs (Sus scrofa f. domestica) in Greece, using the PCR-RFLP method on melanocortin-1 receptor (MC1R) mutations

The melanocortin-1 receptor (MC1R) regulates melanogenesis in mammals within the mammalian melanocyte and the hair follicle. Common variations (polymorph isms) in the MC1R gene are associated with normal differences in skill and hair colour. So far, a unique MC1R allele (E+) has been identified in European wild boar (Sus scrofa scrofa), associated with the wild-type coat colour (variable shades of brown) that is not found in any of the domestic breeds. In addition, a series of alleles found in pigs, some of which observed only in particular breeds, have been proposed as markers in breed traceability systems. The current study is an attempt to detect possible hybrids between wild boars and domestic pig breeds as well as to identify races of pig that are not purebred. For this purpose, wild boars were analysed against Large White pigs, applying the PCR-restriction fragment length polymorphism (RFLP) method. A high percentage (16.7%) of hybrids was detected within a breeding station compared with the percentage of hybrids within the populations of free-ranging wild boar (5.0%). These results should be taken into consideration for future restocking operations to avoid the chance of outbreeding depression, which is more intense when local Populations are introgressed by gene pools from domesticated, usually inbred, animals. (C) 2008 Deutsche Gesellschaft fur Saugetierkunde. Published by Elsevier GmbH. All rights reserved

Regulation of expression of the p21CIP1 gene by the transcription factor ZNF217 and MDM2

Using mouse double minute 2 (MDM2) protein-specific affinity chromatography and mass spectrometry, we have isolated the protein product of the oncogene znf217, which is a transcription factor and a component of a Hela-S-derived HDAC1 complex, as a novel MDM2-interacting protein. When co-expressed in cultured cancer cells, ZNF217 forms a complex with MDM2 and its ectopic over-expression reduces the steady-state levels of acetylated p53 in cell lines, suppressing its ability to activate the expression of a p21 promoter construct. In-silico analysis of the p21 promoter revealed the presence of several ZNF217-binding sites. These findings suggest that MDM2 controls p21 expression by at least 2 mechanisms: through ZNF217-mediated recruitment of HDAC1/MDM2 activity, which inhibits p53 acetylation; and through direct interaction with its binding site(s) on the p21 promoter. © 2016 Published by NRC Research Press

Analysis of MC1R genetic variation in Lepus species in Mediterranean refugia

A study on the inter- and intraspecies variation of MC1R gene was performed in Lepus species inhabiting the Mediterranean basin (L granatansis, L europaeus, L. corsicanus, L castroviejoi and L mediterraneus) and their neighboring species in Europe (L timidus) and Africa (L saxatilis, L capensis), in order to infer micro- versus macroevolutionary adaptation. Eleven different sequences were isolated that corresponded to five amino acid sequences. Comparison of MC1R nucleotide phylogenetic tree with phylogenies resulting from mtDNA regions of the same species showed absence of congruence between these sets of markers. The Mediterranean area that offered refugia during last glaciation retains more MC1R genotypes compared with populations of North and Central Europe as a consequence of founder effects. L corsicanus and L castroviejoi bore identical alleles supportive of their conspecificity, as indicated by other molecular markers. Within L. europaeus, a group of Israeli hares were distinguished by a different MC1R functional allele; additional differences in coat colour and other genetic markers raise doubts about its taxonomic status. Finally, the present data reinforced the idea of bi-directional introgressive hybridization between L europaeus and L. timidus in Switzerland. (C) 2012 Deutsche Gesellschaft fur Saugetierkunde. Published by Elsevier GmbH. All rights reserved

Genetic variation in the major histocompatibility complex of the European brown hare (Lepus europaeus) across distinct phylogeographic areas

The major histocompatibility complex is one of the best studied systems in vertebrates providing evidence for the long-term action of selection. Here, we examined the intra- and inter-population genetic diversity of the MHC class II DRB locus in European brown hare (Lepus europaeus) and correlated the results with genetic variability already estimated from the MHC DQA locus and from maternally (mitochondrial DNA (mtDNA)) and biparentally (allozymes, microsatellites) inherited loci. L. europaeus showed remarkable genetic polymorphism in both DQA and DRB1 loci. The Anatolian populations exhibited the highest genetic polymorphism for both loci. Balancing selection has established increased variability in the European populations despite the founder effects after the last glaciation. Different evolutionary rates were traced for DRB1 and DQA loci, as evidenced by the higher number of common DRB1 than DQA alleles and the greater differences between DRB1 alleles with common origin in comparison with DQA alleles. The high number of rare alleles with low frequencies detected implies that frequency-dependent selection drives MHC evolution in the brown hare through the advantage of rare alleles. Both loci were under the influence of positive selection within the peptide-binding region. The functional polymorphism, recorded as amino acid substitutions within the binding pockets, fell also within distinct geographic patterns, yet it was much narrower than the genetic polymorphism. We hypothesize that certain structural and functional characteristics of the binding pockets set limitations to the actual shape of genetic polymorphism in MHC

Genetic evidence for introgression between domestic pigs and wild boars (Sus scrofa) in Belgium and Luxembourg: a comparative approach with multiple marker systems

Hybridization between wild species and their domestic relatives can be an important conservation and management problem. Genetic purity of the wild species is desirable per se and the phenomenon can have unpredictable evolutionary consequences. Declining European wild boar populations were frequently restocked with farmed wild boars that sometimes had been crossed with domestic pigs. We used simple polymerase chain reaction-based diagnostic tests to detect the presence of mitochondrial DNA and coat colour alleles of domestic origin in wild boars from Belgium, Luxembourg, and western Germany. Microsatellite genotypes were used to test for genetic admixture between the wild boars and domestic pigs. Although almost one-third of all Luxembourg wild boars carried Asian mitochondrial DNA haplotypes originating from domestic pigs, microsatellite-based clustering only identified four putatively admixed individuals in Luxembourg. By contrast, clustering identified wild boar x domestic hybrids in most sampling locations in Belgium. We interpret these results as evidence of releases of hybrid captive-reared wild boars. Our results emphasize the need (if working with classical markers) to use different systems to obtain an understanding as to whether hybridization between wild and domestic relatives might have affected the genetic make-up of a local population.(c) 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110, 104-115

Domestication does not narrow MHC diversity in Sus scrofa

The Major Histocompatibility Complex (MHC) is a multigene family of outstanding polymorphism. MHC molecules bind antigenic peptides in the peptide-binding region (PBR) that consists of five binding pockets (P). In this study, we compared the genetic diversity of domestic pigs to that of the modern representatives of their wild ancestors, the wild boar, in two MHC loci, the oligomorphic DQA and the polymorphic DRB1. MHC nucleotide polymorphism was compared with the actual functional polymorphism in the PBR and the binding pockets P1, P4, P6, P7, and P9. The analysis of approximately 200 wild boars collected throughout Europe and 120 domestic pigs from four breeds (three pureblood, Pietrain, Leicoma, and Landrace, and one mixed Danbred) revealed that wild boars and domestic pigs share the same levels of nucleotide and amino acid polymorphism, allelic richness, and heterozygosity. Domestication did not appear to act as a bottleneck that would narrow MHC diversity. Although the pattern of polymorphism was uniform between the two loci, the magnitude of polymorphism was different. For both loci, most of the polymorphism was located in the PBR region and the presence of positive selection was supported by a statistically significant excess of nonsynonymous substitutions over synonymous substitutions in the PBR. P4 and P6 were the most polymorphic binding pockets. Functional polymorphism, i.e., the number and the distribution of pocket variants within and among populations, was significantly narrower than genetic polymorphism, indicative of a hierarchical action of selection pressures on MHC loci

Toll Like Receptor 9 (TLR9) Polymorphism G520R in Sheep Is Associated with Seropositivity for Small Ruminant Lentivirus

Infectious diseases of sheep are of major economic importance causing direct and indirect losses. Among the major sheep infectious agents are Small Ruminant Lentivirus, Chlamydophila abortus and Mycobacterium avium subsp. paratuberculosis infections, mainly due to their worldwide distribution and economic impact that they cause. Based on the differential susceptibility to infectious diseases between and within breeds and on the recent findings regarding the putative involvement of TLR9 in disease susceptibility, the aim of this study was to evaluate the levels of nucleotide variation of TLR9 and its mediator MyD88 in three sheep flocks originated from different breeds and assess their possible association with seropositivity/seronegativity for different infectious agents. The analysis indicated that the change of G to R at codon 520 of TLR9 polypeptide shows a significant association with Small Ruminant Lentivirus seropositivity. This amino-acid substitution, which can result in polarity change, might influence structure and function of LRR17, interfering with ligand binding and thus could be used in studies investigating susceptibility/resistance to Small Ruminant Lentivirus infections in sheep