Molecular & Quantitative Genetics
Major Research Themes
- Molecular genetics of livestock and the application of DNA biotechnology to animal production
Cattle Quantitative Trait Loci (QTL) Mapping
The major research project in the group is the Davies Adelaide-AgResearch Cattle Gene Mapping Project. The purpose of this collaborative project between the University of Adelaide and AgResearch in New Zealand is to map the genes (QTLs) controlling traits of interest in cattle. The aim is to locate these genes so that the traits may be selected in breeding programs by using DNA biotechnology, and ultimately, to identify the genes themselves so they can be studied and manipulated (Figure 1).
To map the genes, progeny from a Limousin x Jersey double backcross are being analysed. The traits being measured range from carcass fat traits to feed efficiency to behaviour to hide characteristics. The project is unique in that the progeny are being raised in 2 environments (Australia and New Zealand) on different diets. The project is consequently one of the largest beef cattle mapping projects in the world.
The project is supported by the JS Davies Bequest, AgResearch New Zealand and Meat & Livestock Australia.
- Sheep and Cattle Gene Mapping
The genome maps of livestock species are currently inadequate for the identification of genes controlling traits of interest. The human genome, on the other hand, is well studied. The goal of this project is to physically map or localise genes to specific chromosomes in sheep and cattle by fluorescence in situ hybridisation (FISH) (Figure 2). By determining the location of the genes, the livestock genomes can then be compared to the human genome. The information extracted can then be used for QTL mapping experiments such as the one described above. This project is collaboration with University of Melbourne and CSIRO Division of Animal Production, and is supported by the JS Davies Bequest and Australian Wool Innovation.
Parentage Testing in Sheep and Cattle
Current methods of parentage testing are too expensive for routine use by commercial producers. The objective of this project is to develop low-cost parentage testing for sheep and cattle by employing the latest DNA biotechnologies such as DNA microarrays or chips (Figure 3). These technologies can be also utilised for DNA diagnostics and trait selection in breeding programs. The project is in collaboration with University of Sydney, Collinsville, South Australian Research & Development Institute and Orchid Biosciences and is supported by the Australian Research Council.
Cattle Functional Genomics
Functional genomics is another approach to the identification of genes controlling traits of interest. The approach is being taken in attempt to isolate the genes involved in the marbling and tenderness of beef (Figure 4). The project is in collaboration with the CSIRO Division of Tropical Animal Production and is supported by the Cooperative Research Centre for Beef Quality.