Genetically Modified Products

The development of the biological science of genetics began in the mid-1800s, when Gregor Mendel (1822–84) studied the characteristics of plants, and peas in particular, over several generations. His studies were followed by the development of hybrids by [Page 178]Luther Burbank (1849–1926) through selective breeding. Between 1945 and 1965, the green revolution in agriculture greatly increased the world's food supply through the use of selective breeding of hybrid seeds, along with large quantities of pesticides and fertilizers.

The great advance in genetics came in 1953, with the discovery of the DNA molecule by James D. Crick (1928–) and Francis Watson (1916–2004). The secret of life is in the DNA, and especially in the genes on the chromosomes. Genes are attached to the DNA double helix. Genes are codes that process the information to manufacture proteins. To synthesize a protein, a complementary RNA molecule is produced. Its sequence orders a specific amino acid sequence of the protein.

As understanding of the DNA molecule advanced, it became apparent that genes contain genetic information that directs the biochemistry of the human body and all other life. In the case of the human genome, there are 23,000 genes on the chromosomes of the human genetic code. Between 1990 and 2003, the human genome was mapped. Since then, many other life-forms—both animal and plant—have been mapped. This information has been used to create genetically modified (GM) foods or breeds of animals.

Knowledge of the genes in food products allows breeders and seed developers to manipulate the genes in a great many ways. In some cases, genes have been removed. In other experiments, genes have been spliced to form new genetic combinations. The ability to manipulate food products or flowers or other biological forms has given scientists powerful tools for creating insect- and disease-resistant strains of plants.

In the 1990s, laboratories began developing GM organisms (GMOs). Some of the GMOs were agricultural seeds that were produced by manipulating genetic material in a variety of seeds. It was discovered that genetic material could be rearranged, and it was also discovered that genes could be eliminated or replaced by genes from other plants or animals. The development of GM crops allowed strains of seeds or livestock to be bred that grew faster and larger and were resistant to insects and disease.

Between the 1990s and 2009, the acreage devoted to GM crops has increased greatly around the world. Over half of such production is in North America. The GM seeds have greatly increased food supplies; however, there have been numerous concerns raised by scientists over this use of GM products. The concerns are centered on the unknown effects of consuming GM foods. Questions were raised concerning the fact that GM foods experience changes in genes. Can these gene changes affect human biology? Can they lead to human genetic changes that would be undesirable? Can the changes in GM products induce cancer? Do they play a role in the great rise of obesity?