The CRISPR uses guide RNA to lead the enzyme Cas9 to a targeted section of DNA for a little nip and tuck. The RNA is chemically paired with the DNA so it can hone in on its goal. Once on target, the Cas9 acts like scissors to snip problem areas of DNA. This process can eliminate genetic diseases such as breast cancer, cystic fibrosis, sickle-cell disease, Tay-Sachs disease, and many more. And as I mentioned before, this device might also be used to insert something into the cut, providing specific advantages to a baby.
WHAT DOES SCIENCE FICTION SAY ABOUT THE ETHICS OF GENE MODIFICATION?
The right of a child to be born to its full potential shall take precedence over all other considerations. It is the state's responsibility to safeguard the legal rights of the intended embryo.
—Thirty-Ninth Amendment to the Constitution ratified July 4, 2051, from Bruce T. Holmes's Anvil of the Heart
In Anvil of the Heart by Bruce T. Holmes, parents who do not optimize the genes of their children do not find themselves in a comfortable situation.
Science fiction is great for examining ethical perils. The 1997 film Gattaca, written and directed by Andrew Niccol, is about gene manipulation beyond disease prevention. The manipulation ensures that children inherit the best traits from their parents. The depth of this movie comes from Vincent Freeman, the main character, overcoming—or rather, escaping—genetic discrimination because he is born the old-fashioned (classical) way.
Quick fact: the word “Gattaca” comes from the first letters of the four nucleobases (biological compounds) of DNA: guanine, adenine, thymine, and cytosine.
Tired? Did you have a long night? Wouldn't it be nice to never need sleep or feel fatigued again? You could be much more productive and successful at your profession. Rodger Camden hopes exactly that for his daughter in Nancy Kress's novel Beggars in Spain. He arranges for her to be genetically modified in utero to grow up never needing sleep.2
Good idea? Maybe. In her story, the trait isn't without problems. The sleepless crowd is discriminated against because it is believed that they have unfair advantages in business. This makes sense. Employers could hire one employee who can work sixteen hours a day instead of two ordinary humans. Populist movements support buying services and products only from normal sleepers. Now imagine the mob's reaction when they learn that a possible added benefit of being sleepless is immortality.
SPEAKING OF IMMORTALITY, IS IT POSSIBLE?
I don't want to achieve immortality through my work: I want to achieve immortality through not dying.
—Woody Allen
The human body carries genes handed down to our children. Our bodies evolved to be disposable, to make room for future generations. New technology has changed all this. Can aging be abolished? Someday answers, “Possibly.” Science fiction answers, “Definitely.”
Plenty of evidence proves that the average human lifespan has increased with healthier diets, better housing, and better medicine. And as discussed above, gene therapy to an embryo still in the womb (or inside a science fiction womb substitute) can have its DNA optimized to extend life by eliminating potential disease.
As they say, “it's all in your genes.” And whoever they are, they are correct. But of course you already knew that from the chapter on evolution. In a Stanford University study of people who have lived at least one hundred years, scientists have uncovered 281 genetic markers that slowed their aging and made this group less susceptible to disease.3
Scientists are learning so much about genes (and still have so much more to learn). The cerebellum ages slower than any other part of the body. The cerebellum is the region of the brain responsible for motor control and cognitive functions. It appears to stop aging around the eighty-year benchmark.4 So if you happen to be one hundred years old, your cerebellum would have been immune to deterioration for the previous twenty years. If researchers can find the genes responsible for this, who knows? Maybe you live forever.
Or we could borrow some advantages from other species. Sea life would be a good start. A Greenland shark is the current record holder for the longest lifespan. Based on carbon found in the shark's eye lenses, one shark was estimated to be 392 years old.5 The bowhead whale can clock up to an impressive two hundred years. As weird as it sounds, the DNA of different species can be combined. Think of the genetically modified glow-in-the-dark cats on YouTube. So maybe we can incorporate this whale trait into our own DNA.
There is nothing in biology yet found that indicates the inevitability of death.
—Richard Feynman
It is in the cells of your body that your genes hang out. It is good that they have a home (they built it), but your cells are another source of aging. They have a limited shelf life (the notable exception being cancer). They can divide until they hit between forty and sixty doublings. This is known as the Hayflick limit, named for Leonard Hayflick. He discovered that, in addition to external wear and tear, the limit on cell division is part of what makes us die.6
It turns out that cells have a memory of sorts. A meter inside the nucleus reminds a normal cell how many divisions it has already gone through. If a group of cells were frozen and thawed out a few weeks later, they would continue dividing right where they left off until they hit their Hayflick limit.
The limit originates from the shortening of the DNA telomeres with each new division. Telomeres are the sheaths at the end of chromosomes. Think of how the aglet at the end of a shoelace frays with wear. As we grow older, our telomeres dwindle, and the “fraying” impairs the immune function. Telomere shorting is a biomarker of aging.
A protein called Gata4 acts like a switch that forces cells to stop growing and dividing.7 As we age, we accumulate more and more of this protein. It might someday be possible to reverse this switch in older humans. This is not for children. It should only be attempted after tissues are finished developing; otherwise, organs won't develop correctly.
Worn-out tissue can also be reconstructed using stem cells. Stem cells are undifferentiated cells capable of differentiating into specialized cells. They have the potential to become any type of cell such as blood cells, skin cells, brain cells, etc. Using stem cells, biologists have successfully grown an organoid that imitates the human midbrain, the part of the brain that regulates hearing, vision, and movement. This organoid can be used to test new medications for Parkinson's disease and other brain diseases.8
IS A LONGER LIFE WORTH IT?
This is up to you. Here are some questions to get you thinking:
Is a longer life expensive? If yes, will the poor revolt?
If older (in terms of age and not body) people don't retire, how do young people get jobs?
If funding is diverted to support the long-lived, what happens to funding for the education of the young?
How would this affect marriage? Can people tolerate each other for eighty to ninety years? Will serial marriage become the norm?
CAN'T GET ENOUGH OF YOURSELF? SEND IN THE CLONES
If your body parts wear down, they can be replaced. Someday it might be common to have replacement organs grown from your own cells. Why stop there? Why not clone your entire body and harvest the organs as needed, or use it as a younger blood donor? It would do wonders for your energy level and recuperative abilities.
Cloning is asexual reproduction from a single ancestor. The clone will be genetically identical to its progenitor; i.e., a cloned human is genetically identical to her parent. If done on a large scale, variation can only occur in the population via mutations.
Cloning today is done using the SCNT method. This stands for somatic cell nuclear transfer. First, the nucleus of an undifferentiated embryonic cell, which contains all of the donor's genetic goodies, is removed. The nucleus is then injected into an egg cell, and a small electrical shock is delivered to start cell division. The embryo is then implanted into a surrogate female and carried to term.
As with a lot of subjects in this chapter, ethical questions arise about cloning. In the future (if not in science
fiction), will growing organs become a business? Should clones be exploited for organ transplant? How about creating a young clone to receive an upload of your mind?
What does individuality mean to a clone? Think of the Philip K. Dick classic, Do Androids Dream of Electric Sheep? This story was adapted into the movie Blade Runner. A lot of time in science fiction, cloning is about identity and slavery.
In the 2009 movie Moon, cloning is a form of slavery. Sam Bell has the lonely job of mining helium-3 on the moon. After three years, when his contract has concluded, he is sent back home to his wife and child.9
Only this never happens. Every three years a new Sam, a clone with the same memories of home and a wife, is woken to begin a three-year contract. The same again, and again. The movie Oblivion (2013) has a similar theme with Jack Harper clones tricked into drone repair on a dying Earth.10 In both movies, there comes a moment when the clones question their identity. Identity is the path to freedom.
The clones in the Star Wars universe have no doubts about who and what they are. They were all grown to become cannon fodder, except the one who goes into bounty hunting.
GENETICS FOR THE ZOMBIE APOCALYPSE
The common cold was the (classical) biological weapon that saved our earthly rear ends in War of the Worlds by H. G. Wells. For us terrestrials, the cold virus is the least of our problems. Today we have weaponized smallpox, anthrax, Ebola, and rice blast (crop disease caused by fungus). You don't need science fiction to imagine military researchers tinkering with the genetics of these organisms to create more powerful weapons.
Now I'm going to cover something possibly worse, the zombie apocalypse. Zombies might make (fictional) scientific sense. In Patient Zero by Johnathan Maberry, people are infected (zombified) by the Seif al Din prion disease. In World War Z by Max Brooks, they are infected with the Solanum virus. In both cases, it is spread by biting.
Zombies exist in nature. Not human ones, at least not yet. For now, I'm talking about zombie ants. Brace yourselves for a horror story. The villain in this story is a fungus spore called Ophiocordyceps. The spore clamps onto an ant that probably was minding its own business. It digs its way into the ant's body and starts growing in the ant's head near the brain.11
At some point, about half the cells in the ant's head will have become Ophiocordyceps. This is when the fungus excretes a mix of chemicals that give it control over its host. The ant is zombified. The zombie is driven to climb a tree and clamp its jaws onto a leaf where it then proceeds to die. A stalk of the fungus sprouts out the body and drops new spores to the ground where they wait for unsuspecting ants so they can repeat the zombie cycle.
If I were forced to come up with a way to create a human zombie, I might try to genetically modify the rabies virus. Rabies infects the central nervous system and drives people to be violent. Now all an evil scientist (not me) would need to do is hybridize rabies with a flu virus to create an airborne contagious disease.
BACTERIA AND VIRUSES TO THE RESCUE
To fight off the zombies or other sundry villains, you might need special capabilities. A lot of super-powered characters pop up in comic books and movies. They appear to be stronger, faster, and more difficult to damage than a simple baseline human such as myself. And unlike the particle accelerator explosions and lightning storms that linked Barry Allen to the speed force in the CW television series The Flash, solid biological science can be used to create a superhero or supervillain.
Bacteriophages, or phages for short, are viruses (sometimes human-made) that seek out and infect bacteria, leaving human cells untouched. They penetrate bacterium and then go into a nonstop multiplying frenzy until the phages burst out. Think of the alien creature bursting out of officer Kane's chest in the movie Alien. Like the victims of the movie, when the phages are done with the bacterium they have invaded, they move on to the next bacterium. You could design a hero immune to specific bacteria strains.
Another type of phage is the macrophage. It is formed from monocytes, one of the groups of white blood cells that surround and digest pathogens and fix damaged tissue. This is a healing factor. Perhaps not Wolverine of the X-Men level, but it isn't too shabby.
Some of nature's greatest nanotechnology tools are viruses. Viruses are equipped with a few proteins and DNA strands, not too much stuff, and yet they are capable of sneaking into host cells and multiplying. With a bit of direction, they are used in gene therapy to deliver a healthy gene to a defective version of the same gene.
Instead of being an ally, some (actually, quite a few) viruses cause problems. For these cases, it is possible to use bacteria as a weapon. As we saw in the evolution chapter, a bacterium is capable of engulfing a virus and storing its DNA sequence. From that point on, if the same virus attacks, all future generations of the bacteria use the memory of the viral DNA to aim killer enzymes at it. This is similar to how scientists can disable genes or insert DNA sequences into an organism.
PARTING COMMENTS
Today's techniques of gene manipulation have begun to remove the randomness of evolution. Humans are taking over the human condition. Both lifespans and happiness can be increased with biological tweaks.
Clones of a human body can be used for organ harvesting or as a vessel into which to download memories. Or in science fictions, as slaves. Badass biology comes with a log of ethical baggage.
CHAPTER 9 BONUS MATERIALS
BONUS 1: CRIME-BUSTING SCIENCE
How about taking some real science and mixing it with science fiction and mystery? Wouldn't it be cool if, without using a police database, a detective could determine the age and gender of a suspect from DNA left at the scene of a crime?
Forensic technology isn't quite there yet, but it's getting close. Researchers at the University at Albany found a chemical biomarker that can be used to estimate age has recently been identified in blood.12 The enzyme reaches its peak level at eighteen years for a female and ten years for a male, and then declines with age. The same research team also found biomarkers that can be used to determine gender.
The same blood might also reveal a personality trait. Researchers have found certain genetic differences between early birds and night owls.13 DNA left behind might reveal whether the person is a morning or evening type.
Now let's try some crime reconstruction. We've seen how blood can help with immediate profiling; now let's add how it might someday help reconstruct the crime. I'm going to go fictional on you and tell you about space detective Clyde Rex. He is assigned to solve a murder on the space-liner Baxalor. The first thing Clyde does is to kick everyone out of the space-liner's luxury cabin because he works alone.
He pulls out a laser scanner loaded with the latest imaging software that recreates blood spatter trajectories. Based on the size of the stain, his equipment can calculate the mass of each blood droplet. Next, he runs an algorithm on his computer pad that traces backward along the paths of every drop. If the crime scene has been cleaned to hide evidence, Clyde could use an infrared camera to detect blood proteins. Not all of this is fiction.
BONUS 2: METAMORPHOSIS
Quick Fact: the DNA of any individual from any species will have the same DNA over its entire life.
So if the DNA of an insect doesn't change over its lifespan, what explains metamorphosis? Metamorphosis is a process through which a mature body becomes different than its adolescent form—unrecognizably different. The answer is hormones.
Hormones are chemical messengers that affect growth and metabolism. They also signal basic needs such as hunger and reproductive urges. For insects in particular, they trigger metamorphosis and encourage a larva to become an adult. In bugs, the hormone ecdysone changes how the creature's DNA expresses itself.
So the DNA remains constant, but hormonal influences change which genes are turned on and to what extent. This drives metamorphosis: cells produce different proteins that slowly cause a physical change. Consider a caterpillar. It chows down on some leaves until it reaches a critical size,
at which point ecdysone is released. For the caterpillar, eating is the environmental trigger for ecdysone. Once again, nature has something to say.
Man is an artifact designed for space travel. He is not designed to remain in his present biologic state any more than a tadpole is designed to remain a tadpole.
—William S. Burroughs
Fig. 10.1. Illustration of a transhuman (cyborg). (iStock Photo/Auris.)
Transhumanism is not only about how we change ourselves biologically, but it is also about how we can integrate our flesh with technology. It can be as simple as an artificial eye that allows its owner to see farther than baseline perception and, when required, to see in the dark. If we go a bit science fiction-y, our hero Hector could pop out his artificial eye and leave it behind. The eye sends encrypted signals directly to his brain, showing him who is following him. If he doesn't like what he sees, he can use his bionic arm to restrain the fiend until the authorities arrive.
Those are illustrations of the big stuff. Don't forget about the small. Nanotechnology can be used not only for repair but to enhance, to make you much better than you were originally. It can increase strength and memory. Or perhaps it really is all about looks. Someday we might be able to alter our features to impress a date or to go undercover as a spy. Say good-bye to plastic surgery. Best of all, none of this is impossible.
A human who has some bodily functions aided by or dependent on mechanics is called a cyborg. This is becoming more and more common in our everyday world. Surgical procedures today are at the point where replacing a knee or hip is considered (important but) mundane. Using advanced technology, doctors can address many types of physical disabilities. Robotic replacements for amputees are being developed that can be controlled using tiny electrodes implanted in the recipient's brain. The electrodes receive signals from the prosthesis, and the patient is able to feel and move fingers.1
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