Folate Fortified Rice by Metabolic Engineering

Rice is responsible for providing 80% of the daily caloric intake of almost 3 billion people. However, it is a poor source of micronutrients and vitamins including folates (vitamin B9). Folate deficiency results to spina bifida (unclosed neural tube) in infants and megaloblastic anemia (immature and dysfunctional red blood cells in the bone marrow) in adults. Folic acid biofortification in rice may prove to be an effective solution in combating folate deficiency especially in developing countries.

A group of scientists from Ghent University in Belgium obtained japonica rice lines with enhanced folate levels by introducing the genes coding for GTPCHI and ADCS (enzymes necessary for the biosynthesis of folates) from Arabidopsis. The transgenic rice lines exhibit similar phenotype and seed-set capabilities with the wild type. The highest level of folate reached in the GM rice lines corresponds to 1,723 mg/100 g fresh weight, the highest folate content reported for plant species thus far. Further studies are being made to introduce the high folate trait to culinary-appreciated indica rice varieties either by breeding or direct transformation. Researchers are also monitoring the storage stability of folic acid, as rice grains are usually stored for long periods of time.

The paper was published by Nature Biotechnology. Read the abstract at http://www.nature.com/nbt/journal/vaop/ncurrent/abs/nbt1351.html or the full paper at http://www.nature.com/nbt/journal/vaop/ncurrent/pdf/nbt1351.pdf