Samples of regular and so-called golden rice are seen in this handout photo from the International Rice Research Institute of the Philippines. The United States Food and Drug Administration (FDA) has approved Golden Rice, the fourth country to give a thumbs-up to a rice strain genetically altered to prevent blindness in children. The rice contains extra genes that make a precursor to vitamin A, which is vital for preventing childhood blindness. A single helping can supply half the recommended daily intake of vitamin A, according to its developers at the International Rice Research Institute in the Philippines. The genes also give it a distinctive golden hue.