Selective breeding for speed in the racehorse has resulted in an unusually high frequency of the C-variant (g.66493737C/T) at the myostatin gene (MSTN) in cohorts of the Thoroughbred horse population ...that are best suited to sprint racing. Here we show using a combination of molecular- and pedigree-based approaches in 593 horses from 22 Eurasian and North-American horse populations, museum specimens from 12 historically important Thoroughbred stallions (b.1764-1930), 330 elite-performing modern Thoroughbreds and 42 samples from three other equid species that the T-allele was ancestral and there was a single introduction of the C-allele at the foundation stages of the Thoroughbred from a British-native mare. Furthermore, we show that although the C-allele was rare among the celebrated racehorses of the 18th and 19th centuries, it has proliferated recently in the population via the stallion Nearctic (b.1954), the sire of the most influential stallion of modern time, Northern Dancer (b.1961).
Diversity patterns of livestock species are informative to the history of agriculture and indicate uniqueness of breeds as relevant for conservation. So far, most studies on cattle have focused on ...mitochondrial and autosomal DNA variation. Previous studies of Y-chromosomal variation, with limited breed panels, identified two Bos taurus (taurine) haplogroups (Y1 and Y2; both composed of several haplotypes) and one Bos indicus (indicine/zebu) haplogroup (Y3), as well as a strong phylogeographic structuring of paternal lineages.
Haplogroup data were collected for 2087 animals from 138 breeds. For 111 breeds, these were resolved further by genotyping microsatellites INRA189 (10 alleles) and BM861 (2 alleles). European cattle carry exclusively taurine haplotypes, with the zebu Y-chromosomes having appreciable frequencies in Southwest Asian populations. Y1 is predominant in northern and north-western Europe, but is also observed in several Iberian breeds, as well as in Southwest Asia. A single Y1 haplotype is predominant in north-central Europe and a single Y2 haplotype in central Europe. In contrast, we found both Y1 and Y2 haplotypes in Britain, the Nordic region and Russia, with the highest Y-chromosomal diversity seen in the Iberian Peninsula.
We propose that the homogeneous Y1 and Y2 regions reflect founder effects associated with the development and expansion of two groups of dairy cattle, the pied or red breeds from the North Sea and Baltic coasts and the spotted, yellow or brown breeds from Switzerland, respectively. The present Y1-Y2 contrast in central Europe coincides with historic, linguistic, religious and cultural boundaries.
Genetics and African Cattle Domestication Stock, Frauke; Gifford-Gonzalez, Diane
The African archaeological review,
03/2013, Letnik:
30, Številka:
1
Journal Article
Recenzirano
Whether cattle domestication occurred independently on the African continent is among the most controversial questions in the Holocene archaeology of northern Africa. One long-established scenario, ...based upon early archaeological evidence, suggested that Africa's earliest cattle derived from several introductions from Southwest Asia through the Nile Valley, or via the Horn of Africa. Based upon archaeofaunal remains retrieved in the late twentieth century, other archaeologists argued that an independent domestication of the African aurochs gave rise to Africa's earliest domestic cattle. Up to now, the genetic data have also been controversial. This paper reviews the archaeological evidence and the scope of debate, and then focuses on the recent contributions of genetic research to clarifying these issues. S'il y'eût eté une domestication independent des bovins dans le continent Africain perdure comme un question conflictuel dans l'archéologie Holocène d'Afrique. Une hypothèse bien établie dans la literature, et bien fondé sur l'évidence archéologique recouvré dans la premier parte du vingtième siècle, est que les bovins plus anciens dans l'Afrique étaient dérivés de plusiers introductions du sud-oest d'Asie au Vallé du Nil o à la Corne de l'Afrique. Autres archéologues, utilisant des témoignages d'archéofaunes retrouvés pendant la dernière parte du vingtième siècle, prétendaient qu'une domestication independente des aurochs autochtones à l'Afrique etait la source du grand betaîl originel du continent. Néanmois l'évidence génétique était sujet a débattre entre les specialists. Cet article commence en résumer les débats et les evidences archéologiques, et après axe sur les contributions récentes des études du génome bovin à élucider l'histoire du grand betaîl dans l'Afrique.
Historic DNA data have the potential to identify phenotypic information otherwise invisible in the historical, archaeological and palaeontological record. In order to determine whether a single ...nucleotide polymorphism typing protocol based on single based extension (SNaPshot™) could produce reliable phenotypic data from historic samples, we genotyped three coat colour markers for a sample of historic Thoroughbred horses for which both phenotypic and correct genotypic information were known from pedigree information in the General Stud Book. Experimental results were consistent with the pedigrees in all cases. Thus we demonstrate that historic DNA techniques can produce reliable phenotypic information from museum specimens.
Background
Despite extensive evidence that exposure to lead from ingested ammunition harms humans and wildlife, and in contravention of European states’ commitments under multilateral environmental ...agreements to minimize lead emissions, lead in hunting ammunition is still poorly regulated in Europe. The proposed restriction on lead gunshot under the REACH regulation is currently discussed for adoption to protect birds in wetlands from lead poisoning. Based on a subsequent investigation report concluding that additional measures are warranted to control the use of lead ammunition in terrestrial environments, ECHA is preparing a new restriction until October 2020. To help inform this process, we describe REACH management instruments and evaluate the effectiveness and enforceability of different legislative alternatives as well as socio-economic aspects of restricting lead shot in comparison to a total ban. We further discuss how the risks and environmental emissions of lead in rifle bullets can be most effectively controlled by legislative provisions in the future.
Results
Among different management tools, restriction was shown to be most effective and appropriate, since imports of lead ammunition would be covered. The partial restriction of lead gunshot limited to wetlands covers only a minor proportion of all lead used in hunting ammunition in the European Union, leaving multiple wildlife species at risk of being poisoned. Moreover, lead shot will be still purchasable throughout the EU. Within Europe, the costs associated with impacts on wildlife, humans and the environment would be considerably lower when switching to alternative gunshot and rifle bullets.
Conclusion
We argue that there is sufficient evidence to justify more effective, economic, and practical legislative provisions under REACH, i.e., restricting the use and placing on the market of lead in hunting ammunition. The enforcement would be significantly facilitated and hunters could easier comply. A crucial step is to define a realistic phasing-out period and chemical composition standards for non-lead substitutes while engaging all stakeholders to improve acceptance and allow adaptation. Until the total restriction enters into force, Member States could consider imposing more stringent national measures. A total restriction would reduce wildlife poisoning, harmonize provisions of national and European laws, and foster any efforts to decelerate loss of biodiversity.
Regarding the great structural variability of the currently expanding group of ionic liquids, it is highly desirable to understand the basic factors affecting their toxicity in different biological ...systems. The present study of a set of 74 ionic liquids with imidazolium, pyrrolidinium, pyridinium, quinolinium, quaternary phosphonium and quaternary ammonium cations and the comparatively small anions
Cl
-
,
Br
-
,
BF
4
-
, or
PF
6
-
demonstrates the influence of the cation lipophilicity on the cytotoxicity in IPC-81 leukemia cells from rats. The scope of this correlation is limited to ionic liquids with these or similarly small anions that are sufficiently nonreactive under physiological and chromatographic conditions and whose cation lipophilicity does not exceed a certain threshold.
Background
The European chemicals’ legislation REACH aims to protect man and the environment from substances of very high concern (SVHC). Chemicals like endocrine disruptors (EDs) may be subject to ...authorization. Identification of (potential) EDs with regard to the environment is limited because specific experimental assessments are not standard requirements under REACH. Evidence is based on a combination of in vitro and in vivo experiments (if available), expert judgement, and structural analogy with known EDs.
Objectives
The objectives of this study are to review and refine structural alerts for the indication of potential estrogenic and androgenic endocrine activities based on in vitro studies; to analyze in vivo mammalian long-term reproduction studies with regard to estrogen- and androgen-sensitive endpoints in order to identify potential indicators for endocrine activity with regard to the environment; to assess the consistency of potential estrogenic and androgenic endocrine activities based on in vitro assays and in vivo mammalian long-term reproduction studies and fish life-cycle tests; and to evaluate structural alerts, in vitro assays, and in vivo mammalian long-term reproduction studies for the indication of potential estrogenic and androgenic endocrine disruptors in fish.
Results
Screening for potential endocrine activities in fish via estrogenic and androgenic modes of action based on structural alerts provides similar information as in vitro receptor-mediated assays. Additional evidence can be obtained from in vivo mammalian long-term reproduction studies. Conclusive confirmation is possible with fish life-cycle tests. Application of structural alerts to the more than 33,000 discrete organic compounds of the EINECS inventory indicated 3585 chemicals (approx. 11%) as potential candidates for estrogenic and androgenic effects that should be further investigated. Endocrine activities of the remaining substances cannot be excluded; however, because the structural alerts perform much better for substances with (very) high estrogenic and androgenic activities, there is reasonable probability that the most hazardous candidates have been identified.
Conclusions
The combination of structural alerts, in vitro receptor-based assays, and in vivo mammalian studies may support the priority setting for further assessments of chemicals with potential environmental hazards due to estrogenic and androgenic activities.
Background, aim and scope
Due to a number of drawbacks associated with the previous regime for the assessment of new and existing chemicals, the European Union established a new regulation concerning ...the registration, evaluation, authorisation and restriction of chemicals (REACH). All relevant industrial chemicals must now be assessed. Instead of the authorities, industry itself is responsible for the risk assessment. To achieve better and more efficient assessments while reducing animal testing, all information—standard, non-standard and non-testing—has to be used in an integrated manner. To meet these challenges, the current technical guidance documents for risk assessment of new and existing chemicals had to be updated and extended considerably. This was done by experts in a number of REACH Implementation Projects. This paper presents the most relevant results of the expert Endpoint Working Group on Aquatic Toxicity in order to illustrate the change of paradigm in the future assessment of hazards to the aquatic environment by chemical substances.
Main features and challenges
REACH sets certain minimum data requirements in order to achieve a high level of protection for human health and the environment. It encourages the assessor to use alternative information instead of or in addition to standard one. This information has to be equivalent to the standard information requirement and adequate to draw overall conclusions with respect to the regulatory endpoints classification and labelling, persistent, bioaccumulative and toxic (PBT) assessment and predicted no-effect concentrations (PNEC) derivation. The main task of the expert working group was to develop guidance on how to evaluate the toxicity of a substance based on integration of information from different sources and of various degrees of uncertainty in a weight of evidence approach.
Integrated testing and intelligent assessment
In order to verify the equivalence and adequacy of different types of information, a flexible sequence of steps was proposed, covering characterisation of the substance, analysis of modes of action, identification of possible analogues, evaluation of existing in vivo and in vitro testing data as well as of QSAR results. Finally, all available data from the different steps have to be integrated to come to an overall conclusion on the toxicity of the substance. This weight of evidence approach is the basis for the development of integrated testing strategies (ITS), in that the available evidence can help to determine subsequent testing steps and is essential for an optimal assessment. Its flexibility helps to meet the different requirements for drawing conclusions on the endpoints classification and labelling, PNEC derivation as well as PBT assessment. The integration of all kinds of additional information in a multi-criteria assessment reduces the uncertainties involved with extrapolation to the ecosystem level. The weight of evidence approach is illustrated by practical examples.
Conclusions and perspectives
REACH leads to higher challenges in order to make sound decisions with fewer resources, i.e. to move away from extensive standard testing to an intelligent substance-tailored approach. Expert judgement and integrated thinking are key elements of the weight of evidence concept and ITS, potentially leading to better risk assessments. Important sub-lethal effects such as endocrine disruption, which are not covered by the current procedure, can be considered. Conclusions have to be fully substantiated: Risk communication will be an important aspect of future assessments.
•Consistency in the identification, assessment and management of ED substances is needed.•Scientifically robust weight-of-evidence approaches for regulatory decision making are needed.•More debates ...on socioeconomic benefits in the context of decision making are needed.
A discussion paper was developed by a panel of experts of the German Federal Environment Agency (UBA) contributing to the on-going debate on the identification, assessment and management of endocrine disruptors with a view to protect wildlife according to the EU substance legislation (plant protection products, biocides, industrial chemicals). Based on a critical synthesis of the state-of-the-art regarding regulatory requirements, testing methods, assessment schemes, decision-making criteria and risk management options, we advise an appropriate and consistent implementation of this important subject into existing chemicals legislation in Europe. Our proposal for a balanced risk management of endocrine disruptors essentially advocates transparent regulatory decision making based on a scientifically robust weight of evidence approach and an adequate risk management consistent across different legislations. With respect to the latter, a more explicit consideration of the principle of proportionality of regulatory decision making and socio-economic benefits in the on-going debate is further encouraged.
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