Orange Corn Aims to Fight Vitamin A Deficiency
GMO food is still a hot button topic, honestly for no other reason than fear. Sure Monsanto is a big evil corporation, but the science is only as bad as what you do with it. In the modern fortified world we don’t think about vitamin deficiency or the horrible things that come with it, however vitamin A deficiency is a huge problem in developing countries. To combat this researchers have identified a set of genes that can be used to naturally boost the provitamin A content of corn kernels, a finding that could help combat vitamin A deficiency and macular degeneration in the elderly.
Researchers found gene variations that can be selected to change nutritionally poor white corn into biofortified orange corn with high levels of provitamin A carotenoids – substances that the human body can convert into vitamin A. Vitamin A plays key roles in eye health and the immune system, as well as in the synthesis of certain hormones.
“This study gives us the genetic blueprint to quickly and cost-effectively convert white or yellow corn to orange corn that is rich in carotenoids – and we can do so using natural plant breeding methods, not transgenics,” said Rocheford, the Patterson Endowed Chair of Translational Genomics for Crop Improvement.
Vitamin A deficiency causes blindness in 250,000 to 500,000 children every year, yes I did just say year. Of that half of them die within a year of losing their eyesight, this according to the World Health Organization. The problem most severely affects children in Sub-Saharan Africa, an area in which white corn, which has minimal amounts of provitamin A carotenoids, is a dietary mainstay.
Insufficient carotenoid are also been linked to macular degeneration in the elderly, a leading cause of blindness in older populations in Europe and the U.S.
Identifying the genes that determine carotenoid levels in corn kernels will help plant breeders develop novel biofortifed corn varieties for Africa and the U.S. As an added benefit, the dark orange color of these corn varieties also makes them more culturally acceptable to consumers in African countries where yellow corn is generally fed only to animals.
Previous research has identified two genes that contribute to provitamin A carotenoid levels in corn kernels, but
“we wanted more cookies in the jar for breeders to pick from,” Rocheford said.
The researchers used a combination of statistical analysis and prediction models to identify and assess the potential usefulness of genes associated with carotenoid levels in corn. They evaluated data sets from about 200 genetically diverse lines of corn at varying scopes of investigation – from the entire corn genome to stretches of DNA surrounding small sets of genes. They uncovered four genes that had not previously been linked to carotenoid levels in corn kernels.
Though many genes likely contribute to carotenoid levels in corn, “we’re pretty confident that our previous and current research has now identified several genes that are the major players,” Rocheford said.
Their study found that a combination of visually selecting corn with darker orange kernels and using a number of these favorable genes could be an effective way to rapidly convert white and yellow corn varieties to orange corn with higher levels of provitamin A and total carotenoids.
“We now have the genetic information needed to begin developing a major public-private sector collaboration with the goal of providing orange corn with high levels of provitamin A to farmers throughout Sub-Saharan Africa,” he said.
The study also showed that using a more targeted approach to predicting the usefulness of a small set of genes was as effective as evaluating the whole corn genome.
“Having this smaller list of genes to select for means that we can make the improvement of carotenoid levels in corn a simpler, faster process for plant breeders,” said Brenda Owens, first author of the study.
The research – in collaboration with HarvestPlus and the International Maize and Wheat Improvement Center, also known as CIMMYT – has yielded varieties of orange corn with markedly higher amounts of provitamin A carotenoids. But further efforts to produce even higher levels will be necessary to offset degradation of nutrients after harvest and reduce the amount of corn African consumers would need to eat to attain enough provitamin A.
Varieties of orange corn are currently being grown in Zambia, Zimbabwe, Nigeria and Ghana. An open-pollinated variety of orange corn could be available for organic and local grower operations in the U.S. by 2016. Ideally this orange corn will have a better reception than the other attempt at this, golden rice. Which thanks to the work of Greenpeace, who has single handedly killed young children and caused years of suffering thanks to their misguided efforts and fear mongering.
To be clear, that is not an opinion, that is a fact, vitamin A deficiency might not be a big deal here in the US or the UK. However it is a very real threat with very real consequences in other parts of the world. Greenpeace medaling in the affairs of another country so directly should not have happened and honestly it should be looked at as terrorist actions given the proven safety and health benefits of golden rice.
In short it is disgusting and I sincerely hope that the same fate isn’t in store for orange corn.
Correction: In an effort to be clear, I was contacted by a Perdue science writer who requested that I modify my article, I have since taken out the GMO label in the title in favor of simply orange corn. While I can understand that they might not want to be labeled with something as conscientious as “GMO” I still argue that there is no difference between this corn and my golden rice example in the sense that we are changing the genome of the corn, they are just using different methods to achieve the same end goal.
However I concede that she was correct in that GMO is a loaded term now and for this to succeed they need to be able to distance themselves from that idea. If there has been any confusion because of this I am truly sorry and I will admit that in normal circles and in the general media this is certainly not GMO, these genes are naturally occurring in the corn and are bread using traditional methods for selection.
Again my sincerest apologies and a thank you to Natalie van Hoose for putting up with my stubbornness on the semantics and taking the time to politely correct. Kudos to you in particular and what you guys are trying to do. Good luck with the project!
Owens BF, Lipka AE, Magallanes-Lundback M, Tiede T, Diepenbrock CH, Kandianis CB, Kim E, Cepela J, Mateos-Hernandez M, Buell CR, Buckler ES, DellaPenna D, Gore MA, & Rocheford TR (2014). A Foundation for Provitamin A Biofortification of Maize: Genome-Wide Association and Genomic Prediction Models of Carotenoid Levels. Genetics PMID: 25258377