Skip to main content

Development of sustainable aquaculture of arctic charr.

Deliverables

The result consists of methods for amplification of parts of charr genes GH1, GH2, GtH2 and IGF2 and potentially the same genes in other salmonids. The methods should be useful tools for further genomic studies of charr and related species. At present this result is being exploited in experiments for measuring gene activity in charr by P4. The main use of the methods will be by other researchers. The result consist of description of designs of DNA primers for amplification of GH1, GH2, GtH2 and IGF2 genes in arctic charr and the associated laboratory protocols for amplifications. Information about methods for genomic work with charr is scarce. This result provides useful information to researcher aiming at exploring fish genomes. It will be useful for researchers by delivering already developed procedures and thus avoid repeating tedious experimenting.
The cDNA library consist of cDNA obtained after Suppression Subtractive Hybridisation (SSH) of mRNA from juvenile fish selected for having high or low oxygen consumption rate. The library is accordingly expected to contain cDNA from genes preferentially expressed in individuals with low or high oxygen consumption rate. This library will be a useful tool for further research on gene expression in arctic charr.
The result is knowledge on population genetic structure of arctic charr. It gives information on the degree of genetic diversification between populations in different lakes as well as between different morphs within lakes. The knowledge will be useful for policy makers involved in conservation of charr populations and in preserving genetic resources. It is also useful knowledge for further R&D. The knowledge consists of analyses of population genetic data obtained using DNA micro-satellites. Eight different lakes were sampled and five of these had sympatric morphs. The analyses include Hardy-Weinberg tests, F-statistics and Neis Da genetic distance. The results indicate significant genetic differentiation between charr in different lakes. Sympatric morphs show varying degree of genetic differentiation. This knowledge constitute valuable information that has not been possible to obtain for arctic charr due to lack of appropriate genetic markers. It verifies that DNA micro-satellites are useful in arctic charr genetic research.
Data collected on the phenotypic variation across Arctic charr species will be published. It is expected that this data will make significant contributions to the fields of phenotypic variation, post-glacial evolution and the mechanisms of evolution. Spin-off data that has emerged from work on collections of charr from Ireland, Scotland and Iceland has been that detailed morphological analyses of phenotypic variation across the species has been possible. This data we intend to exploit for publication. Although not fully explored it is likely that the scope and breadth of this data will enable very complex detailed analyses of the species across a wide geographical rage to be achieved. The data will make significant contributions to the field of taxonomy, evolution and mechanisms controlling the expression of alternative phenotypes.
The result is a measurement method that can be used for standardised characterisation of arctic charr populations. The method was developed from data obtained from Irish and Scottish charr. The method includes technical details on how to use head landmarks from photographs in a image analysis system to generate data and how to correct these data for overall size effects and to further process these data using uni-variate and multi-variate statistics.
Collection and genetic and morphometric typing of Arctic charr from lakes across Scotland and Ireland has identified populations that are of very high conservation value. 5 sympatric polymorphic populations have been identified and there are 4 others that require further evaluation. These populations require special protection and/or to be evaluated. In addition a further large number of populations have been identified as being near pristine in conservation terms. All of these populations require protection and or active management. The location of these sites, the reason for their status and a very significant dataset on their abundance, spawning and or status has been compiled. The data is available for use in development of conservation, planning or protection programmes.
The result consists of knowledge about the effect that different allelic forms of the IGF2 gene have on growth in arctic charr. This result will be of considerable interest to researchers in genetics as it shows that normally occurring genetic variation at one genetic locus has a strong effect on the phenotype. The result indicates that further research aiming at finding other variable genes with strong phenotypic effects should be done. The result points to further research needs concerning the IGF2 gene regulation and function in fish. The result consists of knowledge based on data on phenotypic performance of arctic charr under aquaculture conditions linked to genetic data showing associations between allelic forms of the IGF2 gene and growth performance. This result is unique among fish genetic studies and only a few, recently published scientific reports on other animals have been able to demonstrate similar results.
The result is a collection of expressed sequence tags consisting of partially sequenced cDNA clones from arctic charr. Out of 234 EST sequences 146 have been identified. The ESTs may be employed in new research for the isolation of full-length cDNAs for characterisation and expression studies. The ESTs are the partial sequences of cDNA from an arctic charr cDNA library. Out of 234 sequences 146 (62%) have been identified using BLAST and Fasta search programs. The majority of sequences are between 300 and 600bp in length.