High Level Accumulation of Gamma Linolenic Acid in GM Safflower

Gamma linolenic acid (GLA) is an essential fatty acid that has properties associated with several therapheutic applications. It also serves as a precursor for the formation of very long chains of fatty acids. To date, there are only few plant sources of GLA and most of these have poor agronomic properties. Thus, an economical and abundant commercial source of GLA in an existing crop is desirable. This led Cory Nykiforuk of SemBioSys Genetics Inc., Canada and a team of scientists to genetically modify the cultivated species of safflower (Carthamus tinctorius) to boost the GLA levels in the seed oil.

Fifty percent increase of GLA in seed oil was achieved when enzymes from a filamentous fungus (Mortierella alpina) was over-expressed. Safflower expressing enzymes from another fungus (Saprolegnia diclina) showed increased GLA levels of up to 70 percent.

According to the researchers, the differences in the GLA levels is not linked to the gene dosage or the absence of triacylgycerol backbone, but on the differences in the activity of the enzymes from two different sources. At present, these are the highest accumulation levels of a newly introduces fatty acid in a biotech crop. Events from these studies have been commercialized as Sonova^TM 400.

Read the abstract at http://www.springerlink.com/content/461gg1333124038q/.