The process of genetic engineering allows for the structure of genes to be altered. It is a deliberate modification which occurs through the direct manipulation of the genetic material of an organism. DNA is either added or subtracted to produce one or more new traits that were not found in that organism before.
With genetic engineering, it becomes possible to create plants that can resist herbicides while they grow. It also becomes possible to create new threats to our food supply or personal health because viruses and bacteria continue to adapt to the changes that are produced through this process.
Here are the advantages and disadvantages of genetic engineering to consider.
What Are the Advantages of Genetic Engineering?
1. It allows for a faster growth rate.
Genetic engineering allows of plants or animals to be modified so their maturity can occur at a quicker pace. Engineering can allow this maturity to occur outside of the normal growth conditions that are favorable without genetic changes as well. Even if there is higher levels of heat or lower levels of light, it becomes possible to expand what can be grown in those conditions.
2. It can create an extended life.
Genetic modification can help to create resistance to common forms of organism death. Pest resistance can be included into the genetic profiles of plants so they can mature as a crop without any further additives. Animals can have their genetic profiles modified to reduce the risks of common health concerns that may affect the breed or species. This creates the potential for an extended lifespan for each organism.
3. Specific traits can be developed.
Plants and animals can have specific traits developed through genetic engineering that can make them more attractive to use or consumption. Different colors can be created to produce a wider range of produce. Animals can be modified to produce more milk, grow more muscle tissue, or produce different coats so that a wider range of fabrics can be created.
4. New products can be created.
With genetic engineering, new products can be created by adding or combining different profiles together. One example of this is to take a specific product, such as a potato, and alter its profile so that it can produce more nutrients per kcal than without the genetic engineering. This makes it possible for more people to get what they need nutritionally, even if their food access is limited, and this could potentially reduce global food insecurity.
5. Greater yields can be produced.
Genetic engineering can also change the traits of plants or animals so that they produce greater yields per plant. More fruits can be produced per tree, which creates a greater food supply and more profits for a farmer. It also creates the potential for using modified organisms in multiple ways because there is a greater yield available. Modified corn, for example, can be used for specific purposes, such as animal feed, ethanol, or larger cobs for human consumption.
6. Risks to the local water supply are reduced.
Because farmers and growers do not need to apply as many pesticides or herbicides to their croplands due to genetic engineering, fewer applications to the soil need to occur. This protects the local watershed and reduces the risk of an adverse event occurring without risking the yield and profitability that is needed.
7. It is a scientific practice that has been in place for millennia.
Humans in the past may not have been able to directly modify the DNA of a plant or animal in a laboratory, but they still practiced genetic engineering through selective breeding and cross-species or cross-breeding. People would identify specific traits, seek out other plants or animals that had similar traits, and then breed them together to create a specific result. Genetic engineering just speeds up this process and can predict an outcome with greater regularity.
What Are the Disadvantages of Genetic Engineering?
1. The nutritional value of foods can be less.
When animals grow, and mature quickly, the nutritional value of that product can be reduced. This can be seen in poultry products today with the white striping that is found in meat products. That striping is a fat deposit that was created, often in the breast meat, because of the rapid growth of the bird. In chickens, Good Housekeeping reports that this can increase the fat content of the meat consumed by over 220%. At the same time, the amount of protein that is received is also reduced.
2. Pathogens adapt to the new genetic profiles.
Genetic engineering can create a natural resistance against certain pathogens for plants and animals, but the natural evolutionary process is geared toward creating pathways. Bacteria and viruses evolve a resistance to the resistance that is created by the genetic engineering efforts. This causes the pathogens to become stronger and more resistant than they normally would be, potentially creating future health concerns that are unforeseen.
3. There can be negative side effects that are unexpected.
Genetic engineering is guaranteed to make a change. Many of those changes are positive, creating more and healthier foods. Some of those changes, however, can be negative and unexpected. Making a plant become more tolerant to drought might also make that plant become less tolerant to direct sunlight. Animals may be modified to produce more milk, but have a shortened lifespan at the same time so farmers suffer a greater livestock.
4. The amount of diversity developed can be less favorable.
At some point, genetically engineered plants and animals make it “into the wild” and interact with domestic species. This results in a crossing of “natural” and “artificial” organisms. The engineered organisms often dominate, resulting in only a modified species over several generations, reducing the diversity that is available.
5. Copyrighted genetic engineering can have costly consequences.
Many companies copyright their genetic engineering processes or products to maintain their profitability. If a farmer plants genetically modified crops and the pollination process causes another farmer in the field over to have those modified crops grow, there have been precedents for legal actions against the “unauthorized” farmer. This can have several costly consequences, from fewer farmers wanting to work to a higher cost for the seeds that are planted.
6. This knowledge and technology can be easily abused.
At the moment, genetic engineering in humans is being used to treat specific disorders that threaten the health or wellbeing of individuals. In time, the approach in humans could be like what is already being done with plants and animals. Genetic engineering can change specific traits, which could create human outcomes that are ethically questionable or easily abused.
The advantages and disadvantages of genetic engineering show that the results can be generally positive, but there must be controls in place to manage the negative when it occurs.
From time to time, science troubles philosophers with difficult ethical questions. But none has been as difficult as considering permanently altering the genetic code of future generations. At a meeting that began on Dec. 1 in Washington DC, the world’s leading gene-editing experts met with ethicists, lawyers, and interested members of the public to decide whether it should be done.
Gene-editing tools have existed since 1975, when a meeting of a similar kind was held to discuss the future of genetic technology. But recent developments have made the technology safe enough to consider turning science fiction into reality. In fact, in April, Chinese researchers announcedthat they had conducted experiments to remove genes of an inheritable disease in human embryos (embryos that were alive but damaged, so they could not have become babies).
So the stakes are high. By eliminating “bad” genes from sperm and egg cells—called the “germline”—these tools have the potential to permanently wipe out diseases caused by single mutations in genes, such as cystic fibrosis, Huntington’s disease, or Tay-Sachs.
At the same time, there is huge uncertainty about what could go wrong if seemingly troubling genes are eliminated.
One of the key researchers in the field is Jennifer Doudna at the University of California, Berkeley. She has been touted for a Nobel Prize for the development of CRISPR-Cas9, a highly precise copy-paste genetic tool. In the build-up to the meeting, Doudna made her concerns clear in Nature:
“Human-germline editing for the purposes of creating genome-modified humans should not proceed at this time, partly because of the unknown social consequences, but also because the technology and our knowledge of the human genome are simply not ready to do so safely.”
Her sentiments were echoed in a report released before the meeting by the Center for Genetics and Society. They believe that research in genetic tools must advance, but only through therapy for adults (where genetic modifications are targeted at some cells in the body but not passed on to kids, such as in curing a form of inherited blindness). The report continues:
“But using the same techniques to modify embryos in order to make permanent, irreversible changes to future generations and to our common genetic heritage—the human germline, as it is known—is far more problematic.”
Consider sickle-cell anemia, an occasionally fatal genetic disorder. Its genes, though clearly harmful, have persisted and spread because, while having two copies of the sickle-cell gene causes anemia, having just one copy happens to provide protection against malaria, one of the most deadly diseases in human history. Had we not known about their benefits, eliminating sickle-cell genes would have proved to be a bad idea.
More importantly, there is a worry that once you allow for designer babies you go down a slippery slope. Emily Smith Beitiks, disability researcher at the University of California, San Francisco, said recently:
“These proposed applications raise social justice questions and put us at risk of reviving eugenics—controlled breeding to increase the occurrence of ‘desirable’ heritable characteristics. Who gets to decide what diversity looks like and who is valued?”
But the history of science shows that it is hard to keep such a cat in the bag. Once developed, technologies have a way of finding their way into the hands of those who desire to use them. That worries George Church, a geneticist at Harvard Medical School, who has been a strong voice in this debate since the beginning. In Nature, he writes:
“Banning human-germlined editing could put a damper on the best medical research and instead drive the practice underground to black markets and uncontrolled medical tourism, which are fraught with much greater risk and misapplication.”
And many believe that the risks of gene-editing are not that high anyway. Nathaniel Comfort, a historian of medicine at Johns Hopkins University in Baltimore, writes in Aeon:
“The dishes do not come à la carte. If you believe that made-to-order babies are possible, you oversimplify how genes work.”
That is because abilities, such as intelligence, height, or personality traits, involve thousands of genes. So there may be some things that you cannot genetically enhance much, and certainly not safely. And even knowingly changing the human genome is not as big a deal as some make it out to be, Church notes:
“Offspring do not consent to their parents’ intentional exposure to mutagenic sources that alter the germ line, including chemotherapy, high altitude, and alcohol—nor to decisions that reduce the prospects for future generations, such as misdirected economic investment and environmental mismanagement.”
The meeting ended on Dec. 3, and the committee of organizers—10 scientists and two bioethicists—came to a conclusion on the debate. They believe that the promises of germline editing are too great to scupper future developments. They endorse that research should continue in non-human embryos and “if, in the process of research, early human embryos … undergo gene editing, the modified cells should not be used to establish a pregnancy.” That is because the committee believes that we neither know enough about safety issues to allow any clinical application, nor enough about how society will respond to the use of this technology in humans.
And, yet, perhaps the the last word on the debate should go to a woman in the audience at the meeting. Her child died only six days old after torturous seizures caused by a genetic ailment. She implored the research community, “If you have the skills and the knowledge to eliminate these diseases, then freakin’ do it!”