My BSc (Biochemistry) Honours degree focuses on the Pinus pest Sirex noctilio. Sirex noctilio has spread significantly to numerous non-endemic regions. It has become necessary to determine whether strains, subspecies, and populations have evolved to different levels of aggressiveness, host preferences, and resistance to parasitic modes of control. Microsatellite sequences could provide a key insight into these diversities. Microsatellites are short repeat sequences that can be used as genetic markers in a myriad of molecular biology studies. Their evolution and function within a genome has been a source of great controversy. Studies have been conducted that prove their usefulness within a genome even impacting the formation of diseases and bacterial virulence. They have been shown to be very vulnerable to changes and are thus beneficial in mutational studies with applications in phylogenetics, forensics and ecology to name a few. In the past their development has been laborious but recent developments in technologies are improving their progress and availability as a genetic marker. Cloning before sequencing is the most laborious process of microsatellite development. Traditional methods of sequencing enriched genomic DNA require the development of clones. Recently another system for sequencing has been developed, namely pyrosequencing. Pyrosequencing is a DNA sequencing technique that is based on the detection ofreleased pyrophosphate (PPi) during DNA synthesis.  In a cascade of enzymatic reactions, visible light is generatedthat is proportional to the number ofincorporated nucleotides.The cascade starts with a nucleic acid polymerizationreaction in which inorganic PPi is released as a resµlt of nucleotideincorporation by polymerase. The released PPi is subsequentlyconverted to ATP by the enzyme ATP sulfurylase, which provides the energy requiredto luciferase to oxidize luciferin and generate light. Becausethe added nucleotide is known, the sequence of the template can be determined.

My Honours project involves the use of novel PCR and pyrosequencing based methods to detect microsatellite sequences and use them to develop polymorphic markers that could be used to assess genetic diversity between Sirex noctilio populations.