genetic engineering

Genetic engineering will change everything

Genetic engineering became practical in the 1980s with the invention by Kary Mullis of a method of copying DNA segments called polymerase chain reaction. The copies can be used for studies, tests, and insertion into the DNA of other organisms. There are other, earlier inventions that were necessary, such as the development of enzymes to cut segments of DNA out of a DNA strand. Those segments then could be copied. But the invention of polymerase chain reaction is a good historical marker.

Most Americans have never eaten bread that did not come from hybridized wheat or rye or other cereal grains. Hybridization is the relatively slow method of genetic engineering. Mother Nature’s random mutations and natural selection are slower still. To get the job done quickly, we now have genetic engineering.

There are various ways of injecting DNA into an organism—including you or me. One method is to employ viruses. A virus naturally infects a host by injecting its DNA into cells of the host plant or animal. Scientists can inject recombinant DNA into a virus and then inject the virus into a person or other animal or a plant, so that the virus becomes a tool for injecting engineered DNA into a host.

An important new development in the technology was announced in 2012. It was CRISPR, a gene editing technique derived from the way some bacteria defend themselves against viruses by slicing up the DNA of the viruses with enzymes. It is considered easy, quick and precise, much better than earlier gene editing methods.

What will recombinant DNA technology change? Everything. It already is changing the food we eat. Much wheat, soybeans and corn now is genetically engineered, although not in dramatic ways. The best example is golden rice, a rice engineered to contain beta carotene. Beta carotene gives the rice a yellow-orange color and is converted in the human body to vitamin A. The World Health Organization estimates that vitamin A deficiency affects 230 million children worldwide, and at least one million children per year die of diseases related to this deficiency. Scientists developed it in 1999. It has been denounced by leftist environmental activist groups such as Greenpeace, but it is a model example of how a human health problem can be addressed through genetic engineering.

The elimination of nutrient deficiencies is one series of steps that we will take. Another obvious step is the elimination of diseases caused by genetic flaws. All sorts of diseases are the result of errors in our DNA. Cystic fibrosis and muscular dystrophy are examples of diseases that stem from genetic flaws. Errors in the genetic code cause the immune system to attack the body’s own lung cells (cystic fibrosis) or muscles (muscular dystrophy). What is needed, obviously, is correction of the DNA through engineering.

Other human flaws are not necessarily labeled diseases. Poor eyesight and poor hearing are common enough. But not everyone has these flaws. Why not engineer the DNA of people so that no one has these flaws? Many people struggle with excess weight. In some cases it is genetic, in other cases behavioral. All cases might someday be curable through genetic engineering. When the weight problems are genetic, the genetic code might be corrected. When weight problems are behavioral, there still might be a genetic cure, because the DNA code might be modified to limit the quantity of food that can be metabolized. What if we engineered ourselves to excrete excessive nutrients rather than metabolize them?

What beauties might be engineered, in plants, animals or ourselves? What models of seductive loveliness might be engineered? Insanity might be eliminated to the extent that it is caused by biochemical flaws affecting the brain. Physical weakness—simple weakness—might be eliminated. Strength might become a controllable, adjustable characteristic, like the temperature controlled by your thermostat.

We worry about running out of oil and natural gas and, eventually, coal. They are non-renewable resources. What if we were to genetically engineer fuel crops? Switchgrass may not be a great fuel crop in its natural state, but what if we engineered it to be more useful? Or engineered some other plant as a fuel crop? Plants grown for fuel will not add to the carbon in the atmosphere. For every carbon atom they add to the atmosphere when burned, they substract one atom while growing and absorbing carbon dioxide. A plant as fuel source would be ideal if it had three characteristics: an ability to grow in marginal soils so that it does not compete with food crops for the best land; an ability to grow fast; and chemical characteristics that allow it to break down easily in a distillery for conversion to an alcohol fuel. There are poor people and farmers all over the world who would welcome such a crop. Across the wretchedly poor region of the Sahel in Africa, between the Sahara Desert and the equatorial rainforests, millions of people would welcome fuel crops adapted to their soils and climates. We would be addressing poverty, energy needs, and climate change at the same time.

Warfare will change. Deadly plagues can be developed through genetic engineering, a very real and terrifying possibility. It has been considered and to some degree explored. Many disease bacteria and viruses already can kill effectively. Engineering can make them more effective.

The ultimate frontier for genetic engineering may be the brain. What is intelligence? Whatever it is, we know it combines nature and nurture. That is, intelligence has genetic components (nature) and elements of personal history (nurture). It should be possible to engineer the optimum brain chemistry and growth characteristics for the development of intelligence.

And where would higher intelligence lead? Everywhere. There is no way to guess what greater health and opportunities might be achievable thanks to the inventions derived from higher intelligence.

November 2012