Polyunstaurated fatty acids are long chain fatty acids that include among them the essential omega-3 (n-3) and omega-6 (n-6) acids. The requirement for humans to ingest these as part of a balanced diet is due to the inability to synthesise the pre-cursors of these compounds, linolenic acid (n-3) and linoleic acid (n-6). Once ingested these pre-cursors are then metabolised into a number of key compounds that play vital roles in inflammation, cardiovascular health and normal brain and visual function. In addition it is also beleived that by ingesting the correct ratio of n-3:n-6 acids has many beneficial effects including reduced risk of heart disease and mental health issues. The benefits of supplementary feeding with n-3 and n-6 fatty acids has been studied extensively in infant nutrition. Studies have shown that supplementing infants food with n-3 and n-6 fatty acids can increase attention span, learning capabilities and even increased IQ over children in control groups. Due to these effects it is now reccomended that all infants diets are supplemented with n-3 and n-6 fatty acids. The main source of dietary fatty acids is in seeds, oils and oily fish with fish oil being the most easily adsorbed and metabolised. However, due to the fact that some people do not like to eat fish products, the unsustainablilty of fish stocks and the growing worry about contaimination of the food chain with noxious chemicals much effort has been directed towards a safe, reproducible and environmentally friendly way of producing fatty acids from oleaginous fungi. The fungus Mortierella alpina makes large amounts of fatty acids. This organism has been used commercially for a number of years and has the potential to make large amounts of pure n-3 and n-6 fatty acids. However, due to the lack of robust molecular tools the full potential of this organism has not been achieved. In this project we will devlop the molecular tools to utilise M. alpina as a factory for n-3 and n-6 production.