Playing with Genes Featured Signal of Change: SoC854 February 2016

The genomic revolution has the potential to change the evolutionary landscape, enabling more precise production of genetically engineered crop variants, climate-change mitigation, and animal customization. Although genetic engineering remains somewhat controversial, it has the potential to benefit many people. For example, researchers at the Swedish University of Agricultural Sciences (Uppsala, Sweden) used genetic engineering to create rice plants that yield 43% more grain than do normal rice plants. In addition, the genetically modified (GM) rice plants produce only 0.3% to 10% of the methane emissions that non-GM rice plants produce, thereby mitigating climate change. Despite providing such benefits, genetic modification can have unintended negative consequences. For example, in July 2015, researchers from the International Center for Integrative Systems (Cambridge, Massachusetts) released the results of a study showing that GM soy plants accumulate the carcinogen formaldehyde, because genetic modification reduces or even depletes the plants' glutathione (an antioxidant that typically detoxifies the formaldehyde). Because regulatory oversight in genetic engineering is mostly lacking, biotech companies may begin conducting experimental testing of gene-edited crops in developing countries. In these countries, the need for food may outweigh the impulse to oppose such testing on ethical grounds.

Because regulatory oversight in genetic engineering is mostly lacking, biotech companies may begin conducting experimental testing of gene-edited crops in developing countries.

A new technique that is further advancing and simplifying genetic engineering is CRISPR (clustered regularly interspaced short palindromic repeats). But the emergence of such simple genetic-engineering techniques has enabled the rise of biohackers—amateur scientists who use community labs to conduct genetic experimentation. Current restrictions permit these "scientists" to conduct only low-level genetic testing, but enforcing these restrictions has proved next to impossible. In the wrong hands, genome editing has problematic ethics and security implications. Moral questions about the extent of genetic engineering exist, and proponents of strict ethical guidelines for genetic experimentation believe that scientists already have gone too far. For example, scientists in China are customizing genes in various animals, including goats, pigs, rabbits, rats, and monkeys. In October 2015, the Journal of Molecular Cell Biology published a paper by a team of Chinese scientists who used CRISPR to edit genes in beagle embryos. During their research, the scientists removed the myostatin gene (a muscle inhibitor) to produce an extra-muscular beagle that is ideal for use in hunting, law-enforcement, and military applications. This form of genetic engineering of animals has the potential to create extraordinary possibilities in medicine and agriculture.

Some people may believe that this form of genetic engineering gives humans too much control and fear that gene technologies capable of producing an immediate effect will sideline gradual evolutionary processes. The extent of such human control could move beyond customizing animals' physical features. For example, scientists may be able to create an animal with abnormally high intelligence or alter an animal's genetic makeup to correct a genetic illness. Ethical boundaries could prevent genetic engineering from going too far in mainstream medical applications, but reining in scientific advances that have such massive potential will be difficult.

Researchers at Sun Yat-sen University's (Guangzhou, China) Key Laboratory of Reproductive Medicine of Guangdong Province have already tested one of the most intensely discussed ethical boundaries of CRISPR by using the technique to edit genes in human embryos. The researchers were attempting to eradicate genetic diseases before the birth of a baby; however, they also identified a lack of reliability and specificity with the CRISPR platform, which could result in the introduction of gene mutations. These revelations will likely raise awareness in the genetic-engineering community, prompting researchers to proceed with caution when experimenting with CRISPR-mediated gene editing in clinical applications.

Indeed, the simplicity and power of CRISPR has caused concern among scientists. Many scientists fear that without proper regulation, the technique could result in genetic modifications that have unintended consequences—for example, permanently changing the germ line of an organism and thereby affecting following generations.

Other genetic-engineering techniques may generate less controversy than CRISPR has. For instance, ribonucleic acid interference (RNAi) can silence genes without directly affecting the genome. Scientists originally investigated RNAi as a tool for treating disease, but the technology is now closer to seeing commercialization as an agricultural tool that can create better crops. For example, RNAi-based crop sprays can target and kill specific insects without affecting crops and provide crops with additional nutrients, making them more disease resistant. Experts believe that using RNAi sprays could become a popular alternative to genetically modifying crops. This development has the potential to usher in a farming revolution. Monsanto (Creve Coeur, Missouri) is currently developing an RNAi spray that kills potato beetles, which are highly resistant to common pesticides. The company believes the spray could be ready for the market by 2020; however, some hurdles still exist. Researchers will need to provide evidence that the RNAi sprays have no adverse effects on the environment or the food chain, and regulatory bodies will most certainly need to establish rules and regulations for the use of these new agricultural products.