At the heart of a revolution in our understanding of life on Earth is the ability to go to the source — DNA — and directly read the genetic code. Over the past 30 years, this revolution has been taking place in the sciences of biology and medicine.

You’ve seen evidence of this revolution if you watch detective shows or read books about crime that feature forensic science and DNA evidence. The revolution in biology has also affected your life if you’ve ever wondered about genetically modified organisms (GMOs) in your food supply, if you or someone you know takes insulin as treatment for diabetes, or if you’ve ever heard of the human genome project.

All these components of modern life began with scientists using DNA technology, the tools and techniques used for reading and manipulating the DNA code.

Scientists use DNA technology to try and solve human problems. Scientists can introduce genes from one organism into another organism, causing the second organism to make new proteins.

When scientists combine DNA from two sources in one organism, they say that the organism is recombinant. When scientists alter the genetic code of an organism, like they do with GMOs, they call the process genetic engineering. Scientists use genetic engineering for many reasons, including the following:

  • To introduce genes for pest resistance or increased nutrition into crop plants.

  • To introduce human genes into bacteria so that bacteria can make human proteins like insulin for medicinal use.

  • To introduce normal genes into the cells of people with genetic diseases to help them function normally. (This medical procedure is called gene therapy.)

In addition to genetic engineering, scientists use DNA technology to create DNA fingerprints, which allow scientists to compare the DNA of one organism with another. DNA fingerprinting is useful in many situations, including:

  • Helping to identify relatives

  • Comparing DNA left at crime scenes with that of suspects

  • Creating a reliable marker, or genetic pattern, of a specially bred animal or plant, such as a famous racehorse or a genetically engineered crop plant, in order to track its descendants

The DNA code is also a source of information about genes and how they control the traits of organisms. By reading DNA, scientists hope to further their understanding of all life on Earth and of human diseases:

  • As part of the human genome project, a global team of scientists read the entire DNA code, called the genome, from human cells. The project, which was completed in 2003, basically created a map showing the location of all the genes on human chromosomes, which is enormously helpful to scientists and doctors who want to understand how human genes control body function.

  • People who are at risk for inheriting genetic diseases may seek genetic screening to determine whether they carry genes that put them at greater risk.

  • Even if you're not at risk for a particular genetic disease, and you're just curious about what's in your genes, you can pay a fee and send your DNA off to company that will examine it for you. The company (called 23andme) will give you a report with information about your ancestry and any known links to health risks they uncover in your DNA.