From ancient domestication to modern biotechnology, it may never have been safer than it is today

By Timothy Page

The debate over genetically modified organisms misses a basic truth: every domesticated plant and animal is already genetically modified. The corn we eat, wheat in our bread, cattle in pastures, and dogs in our homes all result from thousands of years of human-directed genetic changes. Modern biotechnology differs from traditional breeding not because it modifies genes, but because it does so more precisely and safely.

Ancient Genetic Engineering

Humans began systematically changing plant and animal genetics about 10,000 years ago during the agricultural revolution¹. The transformation of wild teosinte into modern corn shows just how dramatic these changes were. Teosinte produces tiny seeds in hard cases that barely resemble today’s large corn kernels. Through selective breeding over thousands of years, indigenous Mexican farmers increased kernel size by more than 1,000 times and completely restructured the plant². This required changing hundreds of genes controlling seed development and plant growth.

Wheat underwent equally dramatic changes. Wild wheat drops its seeds when ripe—good for wild plants but bad for farmers trying to harvest. Early farmers selected plants that held onto their seeds, creating varieties completely dependent on humans for survival³. Modern bread wheat contains genetic material from three different species, making it a genetic combination that could never exist in nature⁴.

Animal domestication produced even more striking changes. Dogs show more variety in size and shape than any other mammal, from two-pound Chihuahuas to 200-pound Great Danes⁵. Dairy cows produce milk at levels that would kill wild cattle, requiring genetic changes affecting mammary glands, calcium processing, and energy use⁶. These animals prove that humans have been genetic engineers for millennia.

Problems with Traditional Breeding

Traditional breeding methods work well but have serious limitations and risks often ignored by critics of modern biotechnology. Conventional breeding relies on sexual reproduction, limiting genetic exchange to related species and requiring the transfer of large chromosome chunks containing thousands of genes. This means beneficial traits often come with unwanted characteristics that take generations to remove⁷.

Traditional breeding can also create unintended and dangerous genetic changes. In the 1950s, scientists began deliberately exposing seeds to radiation and chemicals to create random mutations. More than 3,000 crop varieties currently sold worldwide were created this way, including popular wheat, rice, and citrus varieties⁸. These crops enter the market without safety testing, despite carrying unknown genetic changes.

The famous “killer bee” disaster illustrates the risks of traditional breeding gone wrong. In 1956, Brazilian researchers imported aggressive African honeybees to breed with gentler European bees, hoping to create better honey producers. Instead, the African bees escaped and spread throughout the Americas, creating hybrid “killer bees” that are far more aggressive than either parent species⁹. This conventional crossbreeding experiment created a public health threat that persists today, demonstrating how traditional methods can produce unpredictable and harmful results.

Changes in wheat through conventional breeding may have contributed to increased gluten sensitivity, though this remains debated¹⁰. Regardless, this shows how traditional breeding can alter food chemistry in ways that affect human health, often without systematic testing.

Why Modern Methods Are Better

Modern genetic engineering offers major advantages over traditional breeding in precision, predictability, and safety testing. Unlike conventional breeding, which shuffles thousands of genes at once, molecular techniques can make specific, targeted changes while leaving the rest of the genome alone. This precision reduces unintended effects and allows for more focused improvements¹¹.

Golden Rice shows how precise modern techniques can be. Regular rice can’t produce beta-carotene (which becomes vitamin A) in its edible parts, and traditional breeding failed because the necessary genes don’t exist in rice. Genetic engineering allowed scientists to add just three genes from other organisms, enabling rice to produce beta-carotene without changing anything else about the rice¹². This addresses vitamin A deficiency, which blinds hundreds of thousands of children annually.

Modern genetic engineering also enables improvements impossible through traditional breeding. Bt corn produces insect-killing proteins from soil bacteria, eliminating the need for pesticide spraying while targeting only specific pests¹³. Studies show Bt crops can reduce insecticide use by 50-90% while maintaining yields¹⁴. The proteins only affect insects with the right gut chemistry, making them harmless to humans, birds, and beneficial insects like bees¹⁵.

Genetically modified crops undergo extensive safety testing by three federal agencies—FDA, EPA, and USDA—before reaching market¹⁶. This includes testing the inserted genes, protein safety, nutritional content, and environmental impacts. Traditional crops, including those created through radiation, typically enter the market without comparable safety evaluation.

Scientific Evidence and Real-World Results

The scientific consensus on genetically engineered crop safety has strengthened over the past two decades. A comprehensive National Academy of Sciences review of more than 900 studies concluded that genetically engineered crops are as safe as conventionally bred ones¹⁷. The World Health Organization, American Medical Association, and American Association for the Advancement of Science all support the safety of approved GM foods¹⁸.

Real-world evidence from over 25 years of commercial use supports these conclusions. GM crops now grow on over 190 million hectares worldwide—about 13% of global cropland¹⁹. This massive use has produced no documented cases of harm to human health or widespread environmental damage. Studies actually show environmental benefits, including reduced pesticide use, less soil erosion, and lower greenhouse gas emissions²⁰.

Hawaii’s papaya industry provides a perfect example of genetic engineering’s benefits. The papaya ringspot virus threatened to eliminate Hawaiian papaya production in the 1990s, with no natural resistance available. Researchers developed GM papaya resistant to the virus by incorporating viral genes that trigger the plant’s immune system. This approach, impossible through traditional breeding, saved the Hawaiian papaya industry²¹.

Common Myths Debunked

Critics often claim genetic engineering is fundamentally different from traditional breeding because it crosses species boundaries. But this distinction is less meaningful than it seems. Gene transfer occurs naturally between different organisms through bacteria and viruses²². Traditional breeding also crosses species boundaries—modern wheat contains genes from three different species, and many fruits result from crosses that would never happen in nature.

Some worry that genetic engineering moves “too fast” compared to traditional breeding. Actually, regulatory approval for GM crops typically takes 7-15 years and costs $100-150 million²³. This is longer than development time for many traditionally bred varieties, especially those created through radiation-induced mutations.

The idea that genetic engineering produces “unnatural” foods while traditional breeding works with “natural” variation ignores reality. Domestication created profound genetic changes, and many traditional techniques like chromosome doubling and radiation-induced mutations are highly artificial. The relevant question isn’t whether modification is “natural,” but whether the results are safe and beneficial.

Looking Forward

New genetic engineering techniques are becoming even more precise. Gene editing tools like CRISPR-Cas9 allow scientists to make specific changes to existing genes rather than introducing foreign DNA²⁴. Some gene-edited crops are molecularly identical to varieties that could arise through traditional breeding, leading several countries to exempt them from biotechnology regulations²⁵.

These technologies offer hope for addressing global challenges that traditional breeding can’t solve alone. Climate change is shifting growing conditions faster than conventional breeding can adapt crops, while a growing population needs sustainable agriculture. Genetic engineering can help develop crops more resilient to drought, heat, and changing pests while reducing agriculture’s environmental impact²⁶.

Enhanced nutrition through genetic engineering also holds promise for fighting malnutrition. Beyond Golden Rice, researchers are developing crops with more iron, zinc, and essential amino acids—improvements difficult or impossible through conventional breeding²⁷. These biofortified crops could help address nutrient deficiencies affecting billions worldwide.

The artificial split between “genetically modified” and “natural” foods obscures reality: all domesticated species result from human-directed genetic change. The corn in our fields, cattle in our pastures, and apples in our orchards all carry genetic modifications distinguishing them from wild ancestors. What has changed is not the fact of genetic modification, but our tools for achieving it.

Modern biotechnology offers greater precision, better safety testing, and the ability to introduce beneficial traits that conventional breeding cannot provide. While questions remain about specific applications, the technology itself represents an evolution of humanity’s 10,000-year partnership with domesticated species. As we face challenges of feeding a growing population while protecting the environment, genetic engineering tools—properly regulated and thoughtfully applied—offer valuable additions to plant breeding.

The choice isn’t between “natural” and “artificial” foods, but between different methods of genetic modification. Evidence suggests modern biotechnology, with its precision and safety oversight, may actually be safer than some traditional breeding methods. By acknowledging that all agriculture relies on genetic modification, we can focus on the real questions: which modifications are beneficial, how do we assess their safety, and how do we use these tools to build a more sustainable and fair food system.

Footnotes

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⁴ Shewry, P. R. (2009). Wheat. Journal of Experimental Botany, 60(6), 1537-1553.

⁵ Wayne, R. K. (1986). Cranial morphology of domestic and wild canids. Evolution, 40(2), 243-261.

⁶ Broom, D. M., Galindo, F. A., & Murgueitio, E. (2013). Sustainable, efficient livestock production with high biodiversity and good welfare for animals. Proceedings of the Royal Society B, 280(1771), 20132025.

⁷ Young, N. D., & Tanksley, S. D. (1989). RFLP analysis of the size of chromosomal segments retained around the Tm-2 locus of tomato during backcross breeding. Theoretical and Applied Genetics, 77(3), 353-359.

⁸ Ahloowalia, B. S., Maluszynski, M., & Nichterlein, K. (2004). Global impact of mutation-derived varieties. Euphytica, 135(2), 187-204.

⁹ Winston, M. L. (1992). Killer Bees: The Africanized Honey Bee in the Americas. Harvard University Press.

¹⁰ Kasarda, D. D. (2013). Can an increase in celiac disease be attributed to an increase in the gluten content of wheat as a consequence of wheat breeding? Journal of Agricultural and Food Chemistry, 61(6), 1155-1159.

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¹¹ Ye, X., Al-Babili, S., Klöti, A., Zhang, J., Lucca, P., Beyer, P., & Potrykus, I. (2000). Engineering the provitamin A (β-carotene) biosynthetic pathway into (carotenoid-free) rice endosperm. Science, 287(5451), 303-305.

¹² Tabashnik, B. E., Brévault, T., & Carrière, Y. (2013). Insect resistance to Bt crops. Journal of Economic Entomology, 106(3), 1068-1079.

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¹⁷ Nicolia, A., Manzo, A., Veronesi, F., & Rosellini, D. (2014). An overview of the last 10 years of genetically engineered crop safety research. Critical Reviews in Biotechnology, 34(1), 77-88.

¹⁸ James, C. (2019). Global Status of Commercialized Biotech/GM Crops in 2019. ISAAA Brief No. 55. ISAAA: Ithaca, NY.

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²⁰ Gonsalves, D. (1998). Control of papaya ringspot virus in papaya: a case study. Annual Review of Phytopathology, 36(1), 415-437.

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²⁴ Jones, H. D. (2015). Regulatory uncertainty over genome editing. Nature Plants, 1(1), 1-3.

²⁵ Ainsworth, C. (2017). Agriculture: A growing concern. Nature, 544(7651), S9-S10.

²⁶ Bouis, H. E., & Saltzman, A. (2017). Improving nutrition through biofortification: a review of evidence from HarvestPlus, 2003 through 2016. Global Food Security, 12, 49-58.