Identification of homologous, homoeologous and paralogous sequence variants in an outbreeding allopolyploid species based on comparison with progenitor taxa.

The combination of homologous, homoeologous and paralogous classes of sequence variation presents major challenges for SNP discovery in outbreeding allopolyploid species. Previous in vitro gene-associated SNP discovery studies in the allotetraploid forage legume white clover (Trifolium repens L.) were vulnerable to such effects, leading to prohibitive levels of attrition during SNP validation.

SNP discovery, validation, haplotype structure and linkage disequilibrium in full-length herbage nutritive quality genes of perennial ryegrass (Lolium perenne L.).

Development of accurate high-throughput molecular marker systems such as SNPs permits evaluation and selection of favourable gene variants to accelerate elite varietal production. SNP discovery in perennial ryegrass has been based on PCR amplification and sequencing of multiple amplicons designed to scan all components of the transcriptional unit. Full-length genes (with complete intron-exon structure and promoter information) corresponding to well-defined biochemical functions such as lignin biosynthesis and oligosaccharide metabolism are ideal for complete SNP haplotype determination.

Gene-associated single nucleotide polymorphism discovery in perennial ryegrass (Lolium perenne L.).

Molecular genetic marker development in perennial ryegrass has largely been dependent on anonymous sequence variation. The availability of a large-scale EST resource permits the development of functionally-associated genetic markers based on SNP variation in candidate genes. Genic SNP loci and associated haplotypes are suitable for implementation in molecular breeding of outbreeding forage species.

Cloning and expression of the major secreted cathepsin B-like protein from juvenile Fasciola hepatica and analysis of immunogenicity following liver fluke infection.

The functions of the cathepsin B-like proteases in liver flukes are unknown and analysis has been hindered by a lack of protein for study, since the protein is produced in small amounts by juvenile flukes. To circumvent this, we isolated and characterized a cDNA encoding the major secreted cathepsin B from Fasciola hepatica. The predicted preproprotein is 339 amino acids in length, with the mature protease predicted to be 254 amino acids long, and shows significant similarity to parasite and mammalian cathepsin B.