Rice Enrichment by Genetic Engineering for Combating Iron and Zinc Deficiency

Iron deficiency anemia and zinc deficiency are among the most recognized forms of micronutrient malnutrition and about two billion of people around the world suffer from it.  Monotonous diets based on staple cereals are in fact a poor source of iron and zinc. Rice is a staple food for more than half of the world's population. Various methods have been proposed for food enrichment, but many of them are not effective for biological and socio-economic reasons. Conventional methods used to increase the availability of such micronutrients mainly include supplementing certain foods and enriching them. One of the new methods that has attracted a lot of attention is biofortification of cereal grains, such as rice, has therefore emerged as a promising strategy. Traditional breeding alone is not a valid option for rice biofortification in many circumstances, owing to low genetic variability of micronutrients in the rice germplasm. Gene technology offers perspectives for efficiently improving iron and zinc content in rice grain. In this paper the biotechnology strategies used in order to improve rice for iron and zinc content and the genes controlling iron and zinc homeostasis are reviewed.