The field of genetics involves the manipulation of deoxyribonucleic acid (DNA). DNA contains the genetic "code" which determines the inherited traits of living organisms. Removing a section of an organism's DNA and replacing it with that of another organism can alter the characteristics of the organism. Since its inception, genetic engineering has produced a number of important benefits, such as isolating the gene for interferon, a rare substance that may be of great value in the treatment of viral diseases and cancer. Genetic manipulation may someday also provide a cure for birth defects and inherited diseases. Unfortunately, there are also potential dangers involved in this technology. Genetically engineered diseases, more communicable and virulent than any occurring in nature, could potentially be created in the laboratory by accident or maliciously. Such viruses could be used as a dreadful biological weapon. Domestic and international regulations regarding genetic experimentation exist to prevent such a situation from occurring.