Sapporo is selling 250 6-packs of their ultra limited edition Space Beer through a lottery system for 10,000 yen each – but only to people who live in Japan. The proceeds will go to Okayama University for science education. The malting barley used in this beer is of the Haruna Nijo variety, developed by Sapporo. This barley is the 4th generation produced from barley that spent 5 months aboard the International Space Station in the Zvezda Service Module. The hops from Furano, Hokkaido were also from seeds that spent time in space, although I wasn’t able to find out how long they spent up there. This all sounds pretty cool, a simple feel good pro-space research event.
Sure, it’s cool, and I wouldn’t mind having a taste, but my first thought after reading Barley + Space = Space Beer! on Wired was: were there any mutations in the barley or hops that were caused by the exposure to gamma rays, etc while in space? Should the lucky few who get to try it be worried about unintended changes in the barley and hops from gamma rays and other mutagens in space?
Multiple groups in China have been purposefully using the mutagenizing effects of space as a tool to develop new traits in crops including alfalfa and rice. Unfortunately, these researchers have been publishing in Chinese journals and other journals that I don’t have access to. A 2009 paper in Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis called Spaceflight induces both transient and heritable alterations in DNA methylation and gene expression in rice (Oryza sativa L.) has some key ideas in the abstract that can help us consider the potential risks of “space barley” and other “space crops”.
Spaceflight represents a complex environmental condition in which several interacting factors such as cosmic radiation, microgravity and space magnetic fields are involved, which may provoke stress responses and jeopardize genome integrity. … We report here that extensive alteration in both DNA methylation and gene expression occurred in rice plants subjected to a spaceflight … [which] are heritable to progenies at variable frequencies.
The rice that had spent time in space had epigenetic changes that were passed on to the next generation. The changes didn’t have any obvious phenotypes, so it’s possible that similar changes exist in the decedents of space barley that haven’t been detected. Are these changes dangerous? Probably not, but it is possible. All mutagens (and even just breeding) can cause unintended changes, but testing is not required for plants resulting from either. Space induced mutations will likely escape regulatory scrutiny as well.
The 2004 book Safety of Genetically Engineered Foods: Approaches to Assessing Unintended Health Effects lists some classic examples of breeding resulting in unintended effects in Chapter 3: Unintended Effects from Breeding, including increases of naturally occurring toxins that are harmful to humans. These unintended consequences are often due to selecting for one trait that inadvertently selects for a different trait that may or may not be related to the first trait. Interestingly, these authors of this book were not able to find any examples of unintended consequences due to mutagenesis. This is likely a result of the same process that removes any unintended changes from plants with genetically engineered traits – lots of breeding. Seems a bit paradoxical, but this sort of breeding isn’t done with the goal of developing new traits. Instead, the goal of post mutageneis or post genetic engineering breeding is to stabilize the trait of interest in a line that already has other desired traits. Other research, notably the 2008 Microarray analyses reveal that plant mutagenesis may induce more transcriptomic changes than transgene insertion, showed that both mutagenesis and genetic engineering can cause unintended changes in gene expression. However, obvious phenotypes may be rare.
In the case of space barley, four generations may have been long enough to revert any mutations that had occurred, especially if most changes are epigenetic as suggested by Spaceflight induces both transient and heritable alterations in DNA methylation and gene expression in rice (Oryza sativa L.). The space hops didn’t have any additional generations, so there is a greater likelihood that any mutations that occurred were still present in the hops that were used to produce the space beer. Does this make space beer more dangerous than non-space beer? Maybe, maybe not. It might be a good idea to at least consider potential changes induced by space, just as we should be considering potential unintended effects from breeding, mutagenesis, and genetic engineering. We might employ a flow chart, such as this one from Chapter 7: Framework, Findings, and Recommendations in Safety of Genetically Engineered Foods: Approaches to Assessing Unintended Health Effects. It’s time to stop treating crops resulting from non biotech modifications as inherently safe, and start comparing the newly modified varieties to their parental varieties. Then, we’ll be sure that space beer, space rice, and a host of up-and-coming products are safe for us to eat and drink.