Genetically engineered plants for feed and food

The main focus of first-generation GE (Genetically Engineered) plants were agronomic traits, such as herbicide tolerance or pest resistance, which benefited mainly farmers. The benefits for human or animal health, when present, were indirect, for instance a reduced mycotoxin content, due to a lower plant colonization by mycotoxigenic fungi, or a reduction in commodity prices, due to higher yield or improved farming practices, translating in increased food availability. At present GE plants with nutritionally interesting traits are becoming available, both for feed and food. Forages with improved digestibility, due to a reduction in lignin, have been obtained and also soybean and cereals with increased content of lysine, methionine and tryptophan have been developed. Other interesting GE plants in the pipeline are corn and soybean with increased resistance to mycotoxins-producing fungi or able to degrade mycotoxins. Another important research trend is the reduction of anti nutritional factors such as phytate, which reduces phosphorus availability and increases environmental impact of livestock, particularly of pigs. Oleaginous crops with altered oil composition are available since many years but, while in previous years the increase of oleic acid content was the main target of genetic engineering, recent research focused to improve the content of the cardiovascular protective omega 3 and 6 fatty acids in seed oil. Other important topics of importance both for human and animal nutrition are the increased content of vitamins (Vit. E, B9 and C), pro-vitamin (β-carotene) and flavonoids, an important component of a health promoting diet. The development of oilseed crops with increased sterol content could be an interesting way for reducing cholesterol uptake in humans. The alteration of starch composition or the accumulation of sugars in different polysaccharides could be used in order to obtain processed foods with a more suitable glycemic index, an important characteristic, especially considering the increasing incidence of diabetes.