These aquaculture-oriented commentaries reflect the opinions of GCL associates -- usually Roger Doyle -- and are not the original abstracts of the papers.  Direct quotations from the papers or abstracts are marked with inverted commas.

8. Maybe QTL mapping can actually be done
QTL for live weight traits in Père David's x red deer interspecies hybrids. 1999. Goosen, G.J.C., K.G. Dodds, M.L. Tate, and P.F. Fenessy. Journal of Heredity 90:643-647.
The authors used interspecies hybrids to locate growth-determining genes on chromosomes (actually, on linkage groups). Showed it can actually be done in animals that have within-population variability and life-spans similar to some aquaculture species, without having to make them homozygous first. Making use of this in a cost-effective broodstock improvement programme would be about 2 orders of magnitude harder. A more promising, high-payoff, QTL study using tilapia species hybrids would be to understand -- and learn how to manipulate -- the sex-determining mechanism(s) in these fish.

7. Genetic changes in stock enhancement
Population structure and impact of supportive breeding inferred from mitochondrial and microsatellite DNA analyses in land-locked Atlantic salmon Salmo salar L. 1997. Tessier, N., L. Bernatchez, and J.M. Wright. Molecular Ecology 6:735-760.
Salmon migrate in and out of 4 rivers that enter a large fresh water lake in Canada. Some of these populations are supplemented by hatchery stock originating in the same rivers. The hatchery stocks show "significant changes in allele frequencies and losses of low-frequency alleles but no reduction in heterozygosity. Estimates of variance and inbreeding population size indicated that susceptibility to genetic drift and inbreeding in one population increased by twofold after only one generation of supplementation. " Note that stock supplementation is a major -- often the only --- fisheries management activity in the fresh waters of many developing countries. Managers need to watch carefully for genetic erosion. Not exactly a recent paper but it hasn't been cited much.

6. Want to measure growth properly???
Analysis of Experimental Data with Repeated Measurements. 1999. Reiczigel, J. Biometrics 55:1059–1063.
Proposes a statistical "permutation test" [easy to do] for sorting out the effect of a treatment on two or more groups of individuals. Looks good for seeing whether breeds respond differently to a change in feed or water quality, when the data consist of before-and-after measurements on individuals. Use PIT tags and get the correct answer to this type of question. jreiczig@ns.univet.hu

5. Frankenfish should be good for you
Genetically modified muddle. 1999. Editorial. Nature Biotechnology 17:311.
Makes the point that major new moves in Europe will prevent retail marketing of genetically modified (GM) products. Sainsbury's supermarket and others. However, the flap is about soybeans and maize which have been modified to aid seed companies, growers, herbicide manufacturers etc., not the end consumers. "GM soybeans? Who needs them?" Unfortunately, the new European laws preclude more nutritious products and lower fat profiles etc., so are potentially harming consumers as well. Need to bring GM products to market which will add value to the end product rather than the producer. Aquaculture should ask itself whether we need faster-growing fish through genetic engineering? Or would some other feature be more attractive and useful to the end consumer? Like for instance....... (can't think of anything offhand).

4. More evidence that sociology messes up the genetics
Genetic changes in Oreochromis shiranus (Trewavas) associated with the early stages of national aquaculture development in Malawi. 1999. Ambali, A. J. D., R. W. Doyle, and D. I Cook. Aquaculture Research 30 (579-588).
Genetic diversity is higher in wild populations than in domesticated populations, and the reduction in diversity is proportional to the time since domestication. This and other genetic changes subsequent to domestication are best explained and predicted by socio-economic factors that influence the behaviour of farmers, rather than by the time-and-distance models of standard population genetics. See #2 for a relevant salmon study.

3. More evidence that economics messes up the genetics
Temporal changes in genetic variation of North European cattle breeds. 1999. Kantanen, J., I. Olsaker, S. Adalsteinsson , K. Sandberg, E. Eythorsdottir, K. Pirhonen, and L.E. Holm. Animal Genetics 30:16-27.
Observed changes in genetic variation in 13 breeds of north European cattle over about 40 years. Nordic breeds may have lost between 1 - 11% of their genetic variation. The [relic] native breeds retain a reasonably high genetic diversity. but their genes contribute less than previously to the genetic variation of the popular production breeds. Presumably this is what is happening in domesticated aquaculture breeds as well -- i.e. those in which the "seed" comes from hatcheries rather than the wild. 

2. People not geography
Microsatellite genetic variation between and within farmed and wild Atlantic salmon (Salmo salar) populations. 1999. Norris, A.T., D.G. Bradley, and E.P. Cunningham. Aquaculture 180:247-264.
The population samples came from Ireland and Norway. The authors infer that intensive breeding practices have eroded genetic variability. They suggest that "founder effects and subsequent selection have had more effect on the genetic differentiation between these strains than geographical separation". This is consistent with the suggestion in Ambali's paper [#4] that socio-economic and ethnic variables -- not the variables that appear directly in classical population genetic models -- are controlling the evolution of our aquaculture breeds.

1. If we don't grow Frankenfish we're going to starve
Much food, many problems. 1999. Trewavas, A. Nature 402:231-232.
Makes a good case for claiming that a new type of agriculture, combining genetic engineering with sustainable farming, is our best hope for the future. If we don't use biotechnology we are going to run out of arable land and water. Trewavas criticizes big agro-business, Greenpeace and organic farming in this short, cross and funny paper. He's a plant biologist but tilapia lovers may recognize his name. Aquaculture gene jockeys can use this paper for ammo.