Genetic Mapping Group

Our group uses genetic and molecular biology techniques to address production-related questions in marine fish aquaculture. The main areas of focus are linkage and quantitative trait loci (QTL) mapping and sex determination.

With Debbie Martin-Robichaud (DFO-St. Andrews), our group has been involved for several years in the development of a genetic linkage map for Atlantic halibut. Microsatellite and AFLP (amplified fragment length polymorphism) markers have been the main types of markers used in map construction. In the Pleurogene project, additional microsatellite and AFLP markers will be developed and mapped. Sequences from the EST survey led by Dr. Susan Douglas (IMB) will be analyzed for additional microsatellites as well as for single nucleotide polymorphisms (SNP) and these markers will be added to the map. We expect to produce a moderate density map (600 - 1000 markers) by the completion of the Pleurogene project.

Microsatellites

The halibut families used for the mapping project have also been measured for a number of traits of interest to halibut producers (e.g., length, width, weight, pigmentation, etc.). QTL for these traits will be identified using the linkage map. Additional fish from these families will also be genotyped to provide QTL for factors from later developmental stages such as sex, growth during production, etc. These QTL will be validated in other halibut families and communicated to our commercial partner, Scotian Halibut, in order to select enhanced broodstock.

A second area of interest in our group is the area of reproduction and sex determination. With Debbie Martin-Robichaud, we will investigate potential biomarkers for egg ripeness and optimal spawning time, critical factors in the success of halibut spawning. As well, we will use real-time PCR, the microarray and in situ hybridization to explore the timing and localization of genes involved in gonad differentiation and development. These experiments are tied to our interest in genes and environmental exposures that influence sex determination in halibut and the development of markers for genotypic sex.

Group leader:

Michael Reith
Senior Research Officer, IMB
Co-Principal Investigator PLEUROGENE
E-mail: Michael.Reith@nrc-cnrc.gc.ca
Telephone: (902) 426-8276
Fax: (902) 426-9413
Institute for Marine Biosciences
National Research Council
1411 Oxford Street
Halifax, Nova Scotia
B3H 3Z1
CANADA

Group members

Left to right:
Makoto Matsuoka Associate Research Officer
Darrin Reid Technical Officer, molecular biology
Michael Reith Senior Research, Officer
Cheryl Smith Technical Officer

Selected Publications

Reid D, Pongsomboon S, Jackson T, McGowan C, Murphy C, Martin-Robichaud D, Reith M (2005)
Microsatellite analysis indicates an absence of population structure among Atlantic halibut (Hippoglossus hippoglossus) in the northwest Atlantic Ocean.
J. Fish Biology, in press
Tvedt HB, Benfey TJ, Martin-Robichaud DJ, McGowan C, Reith M (2005)
Gynogenesis and Sex Determination in Atlantic Halibut (Hippoglossus hippoglossus).
Aquaculture, in press
Flynn, SR, Matsuoka, M, Reith, M, Martin-Robichaud, DJ and Benfey, TJ (2005)
Gynogenesis in shortnose sturgeon, Acipenser brevirostrum, LeSuere.
Aquaculture, in press
Martin-Robichaud, DJ, Reid D, Jackson T, Reith M (2005)
Use of molecular genetic markers in Atlantic halibut broodstock management.
Bull. Aquacult. Assoc. Canada, in press
Herbinger CM, Reith ME, Jackson TR (2003)
DNA markers and aquaculture genetics.
In: "Recent Advances in Marine Biotechnology",
vol. 10 (M. Fingerman and R. Nagabhushanam, eds.),
Science Publishers, New Hampshire, pp. 367-419
Jackson, T.R., Martin-Robichaud, D.J., Reith M. (2003)
Application of DNA markers to the management of Atlantic halibut (Hippoglossus hippoglossus) broodstock.
Aquaculture 220, 245-259
Benfey TJ, Martin-Robichaud DJ, Hendry CI, Sacobie C, Tvedt H, Reith M (2001)
Production of all-female populations of fish for aquaculture.
Bull. Aquacult. Assoc. Canada 100-3, 13-15
Reith M, Munholland J, Kelly J, Finn RN, Fyhn HJ (2001)
Lipovitellins derived from two forms of vitellogenin are differentially processed during oocyte maturation in haddock (Melanogrammus aeglefinus).
J Exp Zool. 291, 58-67