Fighting crime and saving the world's fish stocks might not appear to have a whole lot in common, but both seem to be increasingly reliant on techniques developed by geneticists. Using state-of-the-art techniques, some of which would not be out of place in a modern police forensics laboratory, scientists at Galway-Mayo Institute of Technology (GMIT) are keeping track of what is happening to our fish stocks, writes Matt Egan.
GMIT's Molecular Ecology Research Group is currently analysing DNA samples from north east Atlantic fish stocks, work intended to benefit both the marine environment and the Irish economy. The results will provide the European Union with more accurate information for determining fishing quotas and maintaining stocks.
The scientists are also planning to compare current fish stocks with fish preserved and archived over the past 50 years. These techniques will build upon work initially developed in Canada, where scientists used police forensic procedures to analyse marine DNA samples.
As GMIT team leader Dr Elizabeth Gosling explains, "DNA from a single cell left at the scene of a crime by a murderer can be amplified up to produce a quantity of DNA sufficient for a DNA fingerprint and ultimately the identification of the murder."
A similar procedure enables scientists to magnify and compare tiny DNA samples from fish caught at different times and from different stocks.
"Fish stock" is the term geneticists use to describe a community of fish of the same species, explains Gosling. Fish tend not to mate outside their own stock and as with any closed community, this leads to inbreeding. Because of this inbreeding, scientists can identify genetic traits that are unique to members of a particular stock.
Fish exhibit behavioural patterns that are specific to their stock, says Gosling. For example, some stocks reproduce more slowly than others. GMIT is concerned that such stocks are "likely to be seriously depleted or eliminated" if they are fished too intensively.
To illustrate the damage that can result from poorly managed fisheries, Dr Gosling pointed to the "widely publicised collapse of well-known stocks such as the Peruvian anchovy, the North Sea herring and Newfoundland cod".
"It has been estimated," she states, "that more than 70 per cent of fish stocks require urgent intervention to prevent over-exploitation in order to allow the recovery of over-fished populations. There is a clear need for improved fisheries management based on sound advice."
It is believed that improving the quality of the advice offered to fishery managers can help sustain the important economic role of Ireland's fishing industry. It netted €260 million for the Irish economy, according to 2002 figures from Ireland's Marine Institute quoted by Dr Gosling .
This genetic approach is intended to work in tandem with more traditional techniques whereby scientists identify stocks by examining physical attributes of fish from different areas.
The traditional approach has at times proved less reliable because it focuses on characteristics that according to Dr Gosling can be "influenced by the environment" as well as by breeding. The geneticists, on the other hand, focus on a particular type of gene (known as a "microsatellite") that is not known to be affected by the environment. The project is run jointly with GMIT's Commercial Fisheries Research Group and has received €300,000 from the Department of Education Technological Sector Research Program. Other key personnel include Dr Pauline King, Dr Deirdre Brophy and Dr David McGrath as well as a number of specially appointed post-graduate students.
It is the post-graduates, such as Karen McCrann, who are given the task of catching the fish. This involves manning a Marine Institute research boat as it sails through the North Atlantic to conduct experiments for this and other projects. Dr Gosling, being something of a landlubber, prefers to keep her feet securely on terra firma. "I hate boats!" she admits.
Dr Matt Egan is based at Glasgow's Medical Research Council Social and Public Health Sciences Unit. He is on placement at The Irish Times as a British Association for the Advancement of Science Media Fellow