Science is the key to improving our crops and our farms
By The National Wheat Improvement Committee (NWIC)
From wheat farmers to wheat scientists, we know consumers are yearning for more transparency and trust within their food “system.” We understand those concerns as consumers ourselves. In an effort to give consumers full scientific knowledge of how wheat has been improved over the years, we have worked together to publish a concise response to recent claims made by Dr. William Davis. The National Wheat Improvement Committee has compiled the following responses to Davis’ slander attack on wheat’s breeding and science improvements. Responses were developed with a scientific and historical perspective, utilizing references from peer-reviewed research and input from U.S. and international wheat scientists.
Wheat Breeding & Science
The wheat grown around the world today came from three grassy weed species that naturally hybridized around 10,000 years ago. The past 70 years of wheat breeding have essentially capitalized on the variation provided by wheat’s hybridization thousands of years ago and the natural mutations which occurred over the millennia as the wheat plant spread around the globe. There is no crop plant in the modern, developed world – from grass and garden flowers, to wheat and rice – that is the same as it first existed when the Earth was formed, nor is the environment the same.
There is no mystery to wheat breeding. To breed new varieties, breeders employ two basic methods:
Conventional crossing involves combining genes from complementary wheat plant parents to produce new genetic combinations (not new genes) in the offspring. This may account for slightly higher yield potential or disease and insect resistance relative to the parents.
The second method is to introduce genes indigenous to ancestral or related species of modern-day wheat and gradually incorporate these genes into a new wheat variety with minimal contribution of DNA (typically <5 percent) from the ancestral species. This method still employs crossing, not genetic engineering.
It is very important to realize that either method capitalizes on variation already found in wheat’s lineage.
In the 1960’s, developmental efforts, experimental lines and varieties were shared with researchers around the world. In subsequent years, wheat production in Mexico, India and Pakistan increased tremendously and millions of people who otherwise would have likely died of starvation or malnutrition were able to live and have food. Thus remains the primary goal of today’s wheat breeders - to make this ancient plant meet the demands of a rapidly growing human population. All farmers, including wheat farmers, also rely on plant breeders to develop varieties of seeds that are able to combat constantly evolving pests and diseases and shifting climatic conditions.
In the U.S., scientists working at universities, private companies and the U.S. Department of Agriculture are all committed to research that will help us understand the full breadth of the wheat genome, much like we now have a map of the human genome. This forward motion is desperately needed to find beneficial traits critical to keeping wheat available and affordable. Wheat is not alone, research and breeding are absolutely essential in all food crops because agricultural production must increase by about 66 percent by 2040 to match population growth. Developing healthy plants is necessary to meet the nutritional needs of a growing society.
Wheat breeding utilizes genetic resources previously or currently consumed by the public. New wheat varieties must meet stringent quality standards because wheat is used in such a wide range of products, from breakfast foods like whole grain cereals, to everyday staples such as bread, pizza and noodles, to treats like beer, cake and cookies.
The subsequent Myths & Facts portion will show the inaccuracies of Dr. Davis’ claims.
MYTH: All wheat is the same.
MYTH: The increase in celiac disease is due to wheat breeding.
MYTH: There is a new protein in wheat called gliadin.
MYTH: “Everybody…is susceptible to the gliadin protein that is an opiate. This thing binds into the opiate receptors in your brain and in most people stimulates appetite, such that we consume 440 more calories per day, 365 days per year.”
MYTH: Wheat has been genetically modified.
MYTH: Wheat causes obesity.
Wheat is consumed in 118 countries and the European Union, as measured by USDA. In many other countries with lower levels of obesity, wheat plays a larger role in the diet than in the U.S. For example, the Japanese population has a relatively high daily consumption of wheat (131 g/per capita), yet not a very high prevalence of overweight-obesity (3.2 percent)12. According to the World Health Organization 2010 data, there is no correlation between a country’s per capita wheat production and its obesity rate.
MYTH: Wheat is bad for you.
MYTH: Modern wheat has not been tested for health effects.
MYTH: In Davis’ book he references a study claiming “Wheat gluten proteins, in particular, undergo considerable structural change with hybridization. In one hybridization experiment, fourteen new gluten proteins were identified in the offspring that were not present in either parent wheat plant”15.
Additional information: The variation in high-molecular-weight glutenin-subunit (HMW-GS) sequences reported in this article was induced by somatic cell fusion hybridization, which was performed by isolation of protoplasts of somatic cells, treatment of protoplasts with UV light, fusion of protoplasts, induction of callus and regeneration of plants from the callus tissue16. Both cell culture and UV radiation are procedures used experimentally in a laboratory and can cause genome variation. However, somatic cell hybridization is not a conventional hybridization approach used by wheat breeders17.
MYTH: Wheat is the grain most tied to agribusiness.
Overall, wheat is an essential, safe, healthy and wholesome source of energy and essential nutrients. Globally, 21 percent of the world’s calories come from foods made with wheat. Wheat provides an estimated 4.5 billion people in 94 developing countries 20 percent of their protein intake. In the future, wheat consumption is expected to rise worldwide due to global income growth and urbanization.
The science behind wheat breeding is not a mystery. For decades wheat breeders have been working to improve the integrity and sustainability of the crop. This science has saved millions of lives throughout the world. We encourage consumers to continue learning more about the food they eat and the peer-reviewed science behind the stories and books written. We encourage a constructive dialogue that is based on truth rather than fiction.
For a PDF version of this article, click here.
About The National Wheat Improvement Committee (NWIC)
The National Wheat Improvement Committee is comprised of 24 members representing regional public and private sector researchers, growers and the food processing industry. The goals of the NWIC are to identify and advocate for research priorities of national significance to the wheat community and to provide science-based education on issues which connect wheat improvement with wheat utilization and consumption. Brett Carver, PhD, Regents Professor, Wheat Genetics Chair in Agriculture, Wheat Breeding and Genetics, Oklahoma State University Department of Plant and Soil Sciences serves as the current chair of the NWIC. To learn more about the NWIC, visit http://www.wheatworld.org/research
1 Stephen Baenziger, PhD, Small Grains Breeding and Genetics, University of Nebraska – Lincoln Department of Agronomy
2 David Marshall, PhD, Plant Science Research Leader, USDA-Agricultural Research Service
3 U.S. Wheat Associates
4 Shewry, P.R. (2009). Wheat. Journal of Experimental Botany, 60, 1537-1553). doi:10.1093/jxb/erp058
5 Green, P. (2009). Mortality in Celiac Disease, Intestinal Inflammation, and Gluten Sensitivity. Journal of American Medical Association, 302, 1225-1226. doi:10.1001/jama.2009.1366
6 Cataldo, F., & Montalto, G. (2007). Celiac disease in the developing countries: A new and challenging public health problem. World Journal of Gastroenterology, 13, 2153-2159
7 Wheat Foods Council (Oct. 14, 2011). Gluten and the Diet. Wheat Foods Council. Retrieved from http://wheatfoods.org/resources/gluten-and-diet.
8 Osborne, T.B. (1907). The Proteins of the Wheat Kernel. Carnegie Inst. of Washington Publication, 84, 5-119.
9 Roberto Javier Pena, PhD, Wheat Grain Quality Specialist, International Maize and Wheat Improvement Center (CIMMYT)
10 Jones, J.M. (2012). Wheat Belly—An Analysis of Selected Statements and Basic Theses from the Book. Cereal Foods World, 57, 177-189. doi: 10.1094/cfw-57-4-0177
11 U.S. Department of Agriculture
12 World Health Organization (WHO), 2010
13 European Food Safety Authority Panel on Dietetic Products, Nutrition and Allergies (NDA). (2011). Scientific Opinion on the substantiation of health claims related to arabinoxylan produced from wheat endosperm and reduction of post-prandial glycaemic responses (ID 830) pursuant to Article 13(1) of Regulation (EC) No 1924/2006. EFSA Journal, 9, 2205. doi: 10.2903/j.efsa.2011.2205
14 Hans Braun, PhD, Director of Global Wheat Program, International Maize and Wheat Improvement Center (CIMMYT)
15 Xin, Gao et al. (2009). High frequency of HMW-GS sequence variation through somatic hybridization between Agropyron elongatum and common wheat. Planta, 231, 245-250. doi: 10.1007/s00425-009-1040-1
16 Xia, Guangmin et al. (2003). Asymmetric somatic hybridization between wheat (Triticum aestivum L.) and Agropyron elongatum (Host) Nevishi. Theoretical and Applied Genetics, 107, 299–305. doi:10.1007/s00122-003-1247-7
17 Steven Xu, PhD, geneticist, USDA-Agricultural Research Service
18 JO’Connor, A. An overview of the role of bread in the U.K. diet. Nutrition Bulletin, 37, 193-212. doi: 10.1111/j.1467-3010.2012.01975.x
Other published resources used:
Gregorini, A. et al. (2009). Immunogenicity Characterization of Two Ancient Wheat α-Gliadin Peptides Related to Coeliac Disease. Nutrients, 1, 276-290. doi:10.3390/nu1020276
Graybosch, R.A., et al. (1996). Genotypic and Environmental Modification of Wheat Flour Protein Composition in Relation to End-Use Quality. Crop Science, 36, 296-300.
McKeown, N.M., et al. (2010). Whole-and refined-grain intakes are differentially associated with abdominal visceral and subcutaneous adiposity in healthy adults: the Framingham Heart Study. American Journal of Clinical Nutrition, 92, 1165-71.