Skip to main content

Genetics and Molecular Biotechnology

Main Research Directions

  • Population genetics, phylogeography, systematics, phylogenetics and evolutionary history of marine, freshwater and terrestrial species, with emphasis on deciphering the stock structures of commercially important fish species, using an array of molecular tools
  • Genomics and transcriptomics, to understand the evolution, function and structure of genomes
  • Genotype - phenotype associations and gene mapping in target species to shed light on the genetic basis of traits of commercial interest and fitness characteristics
  • Gene expression in various life stages and environments
  • Microbial diversity and environmental genomics

 

Achievements, applied research

Population genetics - phylogeography

The department has been engaged for some time in the study of genetic variation and stock structure of wild populations of fish species, aiming also at the identification of management units of commercial fish. It plays a leading role in deciphering the phylogenetic patterns and evolutionary history of marine species in the Mediterranean, Atlantic and BlackSeas, shedding light on possible connections between past climate variations, demographic histories, and present-day genetic variation in marine species. The department has produced very successful work in the area of natural populations by applying molecular markers in studies of the genetic structure of marine species, with conclusions of direct relevance to practical applications such as fisheries management and conservation policies. The analysis of the genetic variability of swordfish and anchovy revealed strong population substructuring which is quite an unexpected feature for pelagic species with high dispersal capabilities. There is a long list of other species, whose genetic structure has been investigated by means of molecular genetic markers. The IMBG team has also worked on hake, horse mackerel, gilthead sea bream and striped red mullet, as well as several freshwater and terrestrial species. The synthesis of the multi-species data is actually an important goal to better understand global patterns of biodiversity of marine species.

 

Genetic analysis - farmed stocks

The department has been engaged since the early beginning in the use of molecular genetic techniques to assist genetic improvement in aquaculture, aiming at the production of superior broodstocks of fish for traits such as faster growth, resistance to diseases, and a better understanding of sex determination. Important work has been undertaken on genetic mapping, Quantitative Trait Loci (QTL) analyses and gene expression in aquaculture species. In their acknowledged pioneering work, the team developed and applied for the first time molecular genetic markers (microsatellite DNA) for the parentage identification in a Mediterranean cultivated fish species the gilthead sea bream, Sparus aurata. Recently, the team has played a significant role in the introduction of genomic approaches in aquaculture practices and is actively contributing to practical applications of the produced results in commercial farms.

 

Species identification

The team is experienced in the use of molecular techniques for species and authentication of origin in marine organisms and their products. The team has developed a molecular technique for the identification of shark species, in order to aid traceability of commercially sold dried fins (FAO contract). It has carried out genetic identification of gilthead sea bream, sea bass, and turbot breeders for Greek and Spanish aquaculture companies. Additionally, the team identified through molecular analysis the mislabeling of a hazardous fish species sold to a supermarket chain. Finally, metabarcoding approaches have been used to study environmental samples, e.g. marine microbial communities, stomach contents, and fecal samples.

 

Genomics

The team has embraced the new tools and opportunities that come with next-generation sequencing technologies, and has the bioinformatics expertise necessary to undertake, manage, analyse and interpret the massive data quantities which result. The bioinformatics unit provides a framework within which the diversity of marine life is analysed at all levels of biological organisation, from the gene to the ecosystem. The team was the first in Greece to purchase and operate a next generation sequencing platform (GS FLX pyrosequencer), while continuing to use state-of-the-art Sanger capillary sequencing for small-scale projects and for long-read sequences. Comparative and functional genomics and transcriptomics have been initiated in the team through research in fish. Next-generation sequencing techniques allow the study of the evolution, function and structure of genomes, gene expression, genotype-phenotype associations, and facilitates rapid, cost-effective and large-scale development of new markers such as microsatellites and SNPs.