Genetic engineering is a wonderful and incredibly powerful science, but to many people it’s something that’s still on its way to being a big deal in the future. The truth is that the world of today is very much shaped and influenced by genetic engineering. While the alteration of human beings is still generally taboo and thus limited in practice, there are no such restrictions when it comes to the other branches of the tree of life.
In this article I want to highlight some of the amazing genetic engineering that’s already a fact of life; not just a hypothetical idea which may or may not come to pass. Whether you think these examples are creepy, cool, or just plain wrong, no one can deny that the science behind genetic engineering is impressive.
1. Goats with Spider Genes
We may all be familiar with Spider Pig from the comic books, but a spider goat? Yes indeed, as I’ve mentioned in other pieces on this site, one of the coolest genetic engineering applications has been the splicing of spider genes into the humble goat.
Why? Well, you may have read that spider silk is a very strong substance. It’s actually stronger than steel on a weight-by-weight basis, while being much more flexible. That makes it perfect for all sorts of things such as bulletproof vests, sutures, and car airbags. We get the more familiar type of silk (which is still expensive to produce) by farming the insects themselves. The pupae of the silk moth caterpillars are boiled and processed to get industrial quantities of the stuff. As you can imagine, this is not a process that ends well for the caterpillars, but that’s how it’s done.
It turns out that spiders are about as hard to farm as cats, and getting enough silk out of them is impractical. Synthesis efforts have also failed to yield anything commercially useful. So, in 2010, the results of an ingenious solution were announced. What they’d done was splice spider genes into goats, so that the chemical factories that make their milk also secreted the spider silk protein. The milk can then be processed to extract the silk, although it’s unclear if they can still get cheese out of the deal too.
2. A Lot of Pig Stuff
The poor, long-suffering pig is one of the smartest animals we know of, although not many people think of them that way. Like mice, they are also in many ways very similar to us on a biological level. Unlike mice, pigs are comparable in size to humans, which means we can use them as a direct test-bed for all sorts of genetic methods intended for human applications.
One of the most important tests is being addressed by a team in Japan that is working to a create human-pig chimera – animals that have the genes of two different species.
The reason for this is an attempt to address the serious shortage of donor organs. These chimeric pigs are modified in such a way that certain of their organs will be human, rather than pig, organs. They’re close enough so that the pig could live, but it should also be possible to transplant the organ into a human.
It goes further than this – the ultimate goal of this project is to take skin cells from a human subject and use that DNA to create a pig that will grow organs perfectly matched to that person. That means no organ rejection. Add to this list of pig engineering a project that’s created pigs with way more muscle, and a modification to make them into “micro pigs” that could be sold as pets.
3. Glow in the Dark Animals
Bioluminescence is something that had fascinated humans long before we ever managed to make our own light using methods other than fire. The genetics behind the ability of some animals to make their own light is even more fascinating, and scientists have identified those genes in such a way that the ability can be transferred to other animals through gene splicing.
So now we have glow-in-the-dark mice, sheep, rabbits, pigs (again), monkeys, dogs, cats, and fish. It’s actually not the most complex example of genetic engineering, but to human eyes it certainly is dramatic!
4. Mega Salmon
When we think about GMO or “genetically modified food”, it’s usually GMO crops that come to mind. But our meatier food sources have not escaped the revolution in genetic engineering. Salmon is one of the best, healthiest, and (in my opinion) tastiest protein sources we can eat. Salmon is, however, expensive to catch. And they grow pretty slowly, so farming them is only a bit better.
In this case the gene that was transferred wasn’t from an entirely different species. Instead, this new AquaAdvantage (TM) salmon has a gene from the fast-growing Chinook salmon inserted into it. So now we have aquatic salmon with the size advantage of the Chinook. They grow faster and bigger, which makes them cheaper. More salmon for everyone!
5. Songbird Mice
The Evolved Mouse Project is another Japanese genetic modification outfit that’s splicing all sorts of genes into mice, to learn more about how genes interact and express themselves. One of their experiments has produced a mouse that “sings” or chirps audibly, and much more frequently, than natural mice do. All mice vocalize, but it’s usually at a frequency too high for us to hear. Useful? Probably not, but we sure learn a lot from experiments like these.
6. Vaccine Bananas
Getting vaccinated is incredibly important. Vaccines are almost entirely responsible for eliminating devastating diseases such as polio and rubella from the face of the Earth. Despite a recent, anti-scientific crusade against vaccines, it’s important that people in developing nations get access to them.
Vaccines have to be carefully stored and administered. In countries where refrigeration is scarce and sanitary conditions are non-existent, there has to be a better way to vaccinate people. In 2007, a team of Indian researchers came up with a brilliant idea – bananas; specifically, using bananas to vaccinate people against Hepatitis B. It’s a genius move, but only time will tell how practical and accepted the practice will be.
7. Less Horny Cows
Scientists have not just taken the bull by the horns, they’ve taken the horns entirely. The natural bovine weapon doesn’t have much use on the rolling farm fields of Britain. In fact, five British people reportedly die every year from horn-related injuries.
Usually horns are removed rather crudely to make things safer for workers or people who just wander through a field for some reason. With a little bit of gene editing, there are now cows who don’t grow horns in the first place. In 2016, five perfectly healthy cows had already been born with the horny gene suppressed.
8. Medicinal Chicken Eggs
Despite all the cholesterol scaremongering that’s gone on over the years, it turns out that eggs are still pretty much the closest thing we have to a nutritionally complete food. Now eggs are being considered as another way to make medicines for human beings. In this case, the idea is to modify the hen to produce eggs in which half of the protein in the egg white is replaced with proteins that fight skin cancer. We aren’t supposed to eat the eggs, though – they have to be processed into the drug in order to work.
The main benefit of this is the cheap and easy mass-production of the medicine, which would take much longer and cost much more to synthesize. The kicker is that human genes would have to be spliced into the poultry; technically making them another kind of chimera.
9. Chimeric Milk
Keeping up with that theme, what about cow’s milk that’s the product of human gene splicing? Sound appetizing? Well, it would if you were a human baby. Human breast milk is still the best food for newborns, and artificial formula is still a second-best option in nutritional terms. Many women either can’t or don’t want to produce breast milk. By modifying cows to produce human milk instead of, well, cow milk, it becomes possible to produce it on the same scale as we do cow milk.
10. Scorpion Cabbages
Finally, we can end off with something that doesn’t splice human genes into our food. Instead, we have cabbages that have scorpion genes in them. Way better! In all seriousness, pesticides are a major issue when it comes to modern farming. Farmers need to stop insects from eating the crops meant for us, but spraying a lot of pesticides has a huge effect both on the ecosystem and possibly on us.
The scorpion in question is “Androctonus australis”, a scorpion with venom so toxic that it rivals the deadly black mamba. This critter kills a handful of people every year. Researchers didn’t want to introduce the entire venom into the cabbages. Instead, there is one part of the scorpion’s venom that’s super-effective against insects but harmless to humans. The end result is a cabbage that is safe from destruction by insect pests, that is, until they evolve a resistance to the venom component, which the scorpion might not appreciate very much.
Gross or Great?
If you can’t tell by the rest of my writing in this section, I’m pretty much in favor of clever genetic engineering like this. Of course, my opinion isn’t shared by much of the public, who are grossed out by the idea of transgenics, or transferring genes between species. Putting spider genes into a goat evokes this mad scientist, mutant spider-goat image, but genes are not some sort of “essence”. There’s nothing “spidery” about spider genes. Taken as a totality, the genes for a spider is set of instructions for making a spider. Because all life on earth has a common ancestor, our code is the same. It’s written in the same language. Think of them as the letters of the alphabet. You can arrange the letters to say all sorts of things, but that doesn’t mean taking the “d” from the word “bad” and putting it in the word “good” transfers any of the meaning from one word to the next.
That’s not to say that there are no dangers to this sort of thing. I wanted to highlight that we are already doing some pretty dramatic stuff, and the ethical challenge of genetic engineering is being pushed all the time. There’s always the chance of unintended consequences, and any experiments such as these need to be tested extensively before being let out in the wild.
The science itself is, of course, not good or bad; it all depends on what you do with it. In the end we can’t put the knowledge and power of genetic engineering back into the box. All we can do is to try to use it responsibly to make human life better.
