9781422280751

ADDING GENES TO LIVING THINGS The fragments of DNA are genes or parts of genes. Once identified for their properties, the genes can be added to the DNA of another living thing by using microscopic lifeforms called phages to “carry” them. The phages, which are a type of virus, are put in a flask with copies of the new gene. Some of them take the new gene into themselves. The phages are then added to other cells such as those of an animal. Phages are so small that they can get into a cell and add the new gene to it. The altered cell is then electrically stimulated to divide and make more cells like itself. As it divides and makes more cells, it can even be made to develop into a whole living thing called a transgenic lifeform or genetically modified organism ( GMO ). BENEFITS AND RISKS OF GENETIC ENGINEERING Suppose that scientists study a plant that grows many large seeds. They take out and identify the genes that make the seeds big and numerous. Then they add these genes into another type of plant, where they do not occur naturally. The genes work in their new “home,” and the second plant grows more and bigger seeds. If this plant is a farm crop, this process is, of course, very helpful to the farmer. But genetics is hugely complex. Things can go wrong and o©en do. The rewards may be great, but there could be dangers involved that we cannot even imagine until they happen. THE HUMAN GENOME ORGANIZATION In April 2003, scientists from the Human Genome Organization (HUGO) finished making the list of all the genetic material for a human being. This full set of genes is called the human genome. Bill Clinton, then president of the US, called it “the most wondrous map ever produced by mankind.” Tony Blair, Prime Minister of the United Kingdom (UK), said it was “a breakthrough that opens the way for massive advancement.” Though a major step was taken in genetics for humans, we still do not know exactly what every gene does or how it works.

SIDEBAR

BENEFITS OF GENETIC ENGINEERING FOR HUMANS • Learn about, prevent, and cure many diseases. • Find ways to help wounds heal more quickly. • Discover how we evolved.

• Understand the differences in characteristics between humans. • Identify people from small samples of tissue such as skin or blood.

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