Research Activities                              Go Back!

Laboratory:
Genetic and Conservation Unit, Research Center in Animal Sciences (CECA) and Faculty of Sciences, University of Porto.
Contact person (name and e-mail):
Paulo Alexandrino, palexan@icav.up.pt
Persons working on brown trout population genetics:
Paulo Alexandrino, Agostinho Antunes, Nuno Ferrand
General research topics of the laboratory:
Genetic population structure, conservation and management, phylogeography.
General description of research on brown trout population genetics:
The genetic research on brown trout populations had recently (1994) began at our laboratory. The major research topic is the phylogeography and genetic structure of natural populations, and application of genetic markers in conservation and management of genetic resources. Since stocking of Portuguese brown trout populations is actually made with individuals from authoctonous origin special effort is made in the description and use of highly polymorphic genetic markers for the analysis of microgeographic differentiation and evaluation of restocking programs. Therefore, in addition to the use of highly polymorphic DNA markers, such as microsatellites, we commonly use IEF separation techniques in order to increase the capacity of detection of genetic variability at the protein level and analyse proteins that generally shows highest levels of variability (e.g. plasmatic proteins). This approach will allow to compare the patterns of population genetic differentiation obtained with both microsatellite and protein loci at a microgeographic scale, for which the traditional allozyme loci are not, in general, sufficiently discriminant. This comparison it’s important since the exclusive use of microsatellite loci is problematic due to the incomplete knowledge about their mode of evolution.

Other linked research topics, which are common to other vertebrate species we study in our laboratory, are the investigation at the molecular level of some particular protein genes and haplotype analysis involving protein-microsatellite loci or different microsatellite loci.

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List of projects (brown trout) for the past 3 years:

 

Study #1
Researcher: Agostinho Antunes (PhD. Student), Paulo Alexandrino (supervisor), René Guyomard (co-supervisor)
Source of project funding: MCT, Portugal.
Topic: Phylogeography.
Objective: Study of the phylogeny and genetic structure of Portuguese populations; comparison of phylogenies obtained with allozyme and microsatellite loci; confirmation of actual hypothesis about postglacial colonization’s; studies about the genealogy of some particular genes.
Design: A common battery of protein and microsatellite loci will be used to analyze several brown trout populations covering the all range of distribution of this species in Portugal. The inclusion of other European populations, both from Atlantic and Mediterranean group, will allow a deeper knowledge of the phylogeny of Iberian Atlantic populations. The study of highly polymorphic loci, such as microsatellites and some protein loci analysed by IEF separation techniques, will permit a more correct evaluation of genetic population structure at a microgeographic scale. If possible, ancestrally of alleles from more important protein loci in brown trout studies (e.g. TF), will be determined by sequencing and determination of mutations involved in allelic variants.
Methodology: Allozyme electrophoresis (inclusion of IEF techniques), microsatellites, nDNA sequencing (TF gene).
Trout population: Resident populations.
Origin of samples: North-west Iberian Peninsula, Atlantic Sea Basin, in addition samples from North Sea Basin and Mediterranean Basin.
Status: Started in 1997, planning to finish in 2001.

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Study #2
Researcher: Paulo Alexandrino, Agostinho Antunes, Nuno Ferrand
Source of project funding: FCT, Project PRAXIS, Portugal.
Topic: Genetic population structure, phylogeography, conservation and management.
Objective: Preliminary analysis of genetic structure and phylogeny of Portuguese brown trout populations from River Lima basin and evaluation of restocking actions. This is part of a National Project intitled "Population biology and ecophysiology of salmonid populations from north Portugal".
Design: Analysis of brown trout individuals from 3 tributaries (7 sampling sites) from river Lima basin (north Portugal) and from an hatchery commonly used for restocking programmes. Study of a battery of 22 protein loci with the introduction of isoelectric focusing separation techniques which allows an increasing in the detection of genetic variability.
Methodology: Allozymes, electrophoresis and isoelectric focusing.
Trout population: Resident populations, hatchery stocks (autochtonous origin).
Origin of samples: Portugal, Atlantic Sea Basin.
Status: Started in 1994, planning to finish in 1998.

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Study #3
Researcher: Paulo Alexandrino, Agostinho Antunes
Collaborators: Eva Garcia-Vazquez, J. Suarez, J.L. Martinez, P. Moran (University of Oviedo, Spain)
Source of project funding: Integrated Actions, Portugal-Spain.
Topic: Phylogeography.
Objective: Analysis of latitudinal genetic variation in brown trout populations from the "ancestral" Atlantic group (northwest Iberian) and evaluation of adaptative effects at the population level in the Portuguese populations from the southern limit range of the species.
Design: Comparative study of 10-12 populations distributed from Asturias to northern Portugal, for a common battery of genetic markers.
Methodology: Allozymes, microsatellites, mtDNA RFLP.
Trout population: Resident populations.
Origin of samples: Northwest Iberian Peninsula, Atlantic Sea Basin.
Status: Started in 1998 (1 year, renewable).

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Publications (brown trout genetics)

Theses (eg, PhD and MSc theses):

  • Antunes, A. (1997). Genetic characterization of some brown trout (Salmo trutta) subpopulations from river Lima basin. MSc thesis, University of Porto (in Portuguese).

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