Embryo Project Encyclopedia

Golden Rice was engineered from normal rice by Ingo Potrykus and Peter Beyer in the 1990s to help improve human health. Golden Rice has an engineered multi-gene biochemical pathway in its genome. This pathway produces beta-carotene, a molecule that becomes vitamin A when metabolized by humans. Ingo Potrykus worked at the Swiss Federal Institute of Technology in Zurich, Switzerland, and Peter Beyer worked at University of Freiburg, in Freiburg, Germany. The US Rockefeller Foundation supported their collaboration. The scientists and their collaborators first succeeded in expressing beta-carotene in rice in 1999, and they published the results in 2000. Since then, scientists have improved Golden Rice through laboratory and field trials, but as of 2013 no countries have grown it commercially. Golden Rice is a technology that intersects scientific and ethical debates that extend beyond a grain of rice.

When cells-but not DNA-from two or more genetically distinct individuals combine to form a new individual, the result is called a chimera. Though chimeras occasionally occur in nature, scientists have produced chimeras in a laboratory setting since the 1960s. During the creation of a chimera, the DNA molecules do not exchange genetic material (recombine), unlike in sexual reproduction or in hybrid organisms, which result from genetic material exchanged between two different species. A chimera instead contains discrete cell populations with two unique sets of parental genes. Chimeras can occur when two independent organisms fuse at a cellular level to form one organism, or when a population of cells is transferred from one organism to another. Chimeras created in laboratories have helped scientists to identify developmental mechanisms and processes across species. Some experiments involving chimeras aim to provide further knowledge of immune reactions against disease or to create animal models to understand human disease.