Fish present an astonishing diversity of systems of sex determination and in species with single monofactorial genetic determination, the major determinant present on the sex chromosome is the gene responsible for the start of gonadic differentiation that leads to the formation of male and female gonads. In salmonids, an important family from the aquacultural and environmental point of view, sex determination is of the XX/XY type. We recently identified a gene known as SDY which expresses itself specifically in the embryonic male gonads of the trout and which is genetically strictly linked to the Y chromosome in the rainbow trout and common trout. Our results strongly suggest that SDY is the major sex determinant in these two species and perhaps other salmonids.
The main aims of this project are therefore to :
- characterise the function of SDY in the rainbow trout, by checking if it is really a major sex determinant,
- study its genomic and functional evolution in salmonids.
The identification of the major sex determinant in the rainbow trout will be of the utmost importance in view of the very low number of non-mammalian vertebrate species in whom a major sex determinant gene has been characterised. This project will also have important practical consequences as it will provide a genetic sexing tool for aquaculture, ecotoxicology and ecology.
This project was labellised by the AQUIMER Pole of Competitiveness on the 10th March, 2011.