Last weekend at the International Genetically Engineered Machine (iGEM) World Jamboree hosted at MIT, a group of Hopkins undergraduates presented a strain of yeast that some hope will one day change the way nutritional deficiencies are addressed around the world.
The 18 members of the Hopkins team spent last summer and the beginning of this semester developing a strain of yeast that produces vitamin A when used in traditional bread recipes. By inserting synthetic DNA containing the genes for the enzymes needed to produce vitamin A, the team succeeded in enriching bread they baked in the lab and made the cut to the top "Sweet Sixteen" teams of the 60 teams that advanced to this weekend's World Jamboree.
The iGEM competition is an international synthetic biology challenge founded by MIT in 2004 in which students use and develop standardized gene expression programs to advance biological systems. Each undergraduate team competes to develop the biological system and effectively express it in living cells to address social or scientific problems.
In the tradition of past iGEM projects from other universities, the Hopkins team sought to address a serious world health issue with their genetically modified machine. Past projects have included bacteria that work as biosensors for deadly water parasites or for fertilizer levels, that clean up oil spills and heavy metals or that fight malaria in the guts of mosquitoes and cancer in the heart of tumors.
Although the yeast, termed "VitaYeast," is able to produce enough beta carotene for about 10 percent of daily vitamin A requirement in an entire loaf of bread, the team's work is far from finished.
"So our project is not complete as of yet, but what we did show is proof of concept," junior biomedical engineering major Arjun Khakhar said.
The 2011 iGEM competition is now finished, yet several of the team members plan to continue with the project, ultimately hoping to optimize vitamin A production in the yeast so that a few slices of VitaYeast bread contain enough vitamin A to meet daily nutritional requirements. They are currently seeking additional funding to continue the project.
According to the World Health Organization, Vitamin A deficiency impedes the health and development of 250 million preschool children in the world each year, leading to blindness in approximately one-tenth of these children. Current methods of vitamin A supplementation involve bi-annual administration of high doses of vitamin A to the most vulnerable communities as well as food fortification. These efforts are effective in the communities that they do reach, but leave children of less-accessible rural communities vulnerable to blindness and death induced by the deficiency.
"We could approach different governments to distribute the yeast for their own intervention programs. It's a self-replicating factory for vitamin production," Khakhar said.
Khakhar asserted in a previous interview that the group does not have plans to patent the yeast if it should become an effective vitamin A producer. Even then, distribution of the yeast would face a number of hurdles, including the ethics of its distribution and federal regulatory approval of its safety.
"I think that would be able to get FDA approval because yeast is already considered a safe organism, and the genes that make beta carotene [vitamin A] are already safe. We would only have to show that there is no genetic flow — that the genes in the yeast cannot move out of the organism into you [the consumer]. If we can show this, we should be able to get FDA approval."
The challenge of obtaining FDA approval for VitaYeast may prove to be a small challenge compared to obtaining social approval for its distribution and consumption. Aware of the challenges that arise from public perceptions of anything genetically modified, the team is currently conducting surveys in Baltimore and abroad to evaluate reactions to VitaYeast. Convincing aid agencies and the public that consumption of the genetically modified yeast is both safe and ethical is likely to prove challenging, but if the team were to succeed, this undergraduate-driven endeavor could have far reaching implications for micronutrient distribution programs.
