Archive for the ‘Movie’ Category

h1

Biology of Prometheus

July 5, 2012

The movie Prometheus, which came out June 8, 2012 and is supposed to be a prequel to the Alien series, is about a team of biologists, anthropologists, archaeologists, and spacemen that travel to a planet they suspect holds the origin of our lives, which they heartwarmingly refer to as answers. Their hypothesis is that human culture has been fascinated with a certain star system over millennia, and in that star system is a race of beings they call, “the engineers,” who created us. Their goal is to meet their makers, and figure out why we exist, (or why they made us).

Spoiler alert!

They discover these humanoid engineers, but they are all dead from some experiment gone wrong. The experiment turns out to be some weapon of mass biological warfare intended to destroy human civilization, that ultimately produces the Alien we all know from the original movies.

Spoiler over!

Ultimately, these engineers seem to be some kind of biological engineering experts, and the technology they created, though fictional, are the topic of today’s post. Specifically, I want to discuss how it might work, some issues, and some thoughts I had about it.

What we know.

In the first scene in the movie, they basically show their entire technology/process that led to our creation.

(Note: This clip is not the complete opening)

We see a humanoid man(?) eat some kind of black sushi roe, his blood vessels go crazy, he keels over, then falls into the water. As his body and cells disintegrate, we see his DNA turn black and degrade. Then cells appear with new DNA, and the cells divide in a manner very similar to early developmental cleavage.

We are to assume that these dividing cells lead to human development, but it remains unclear if these cells then evolved, or if those things became little Adam and Eve embryos.

Additionally, later in the movie we see three more similar processes happen. The first involves a man ingesting just one of these black eggs, the second involves a man getting attacked by a large eel (which we should note is the result of the virus infecting little worms), and the final is one of the “engineers” being attacked by a large squid.

In the first of these, they torch the man prior to his development into some kind of creature, while in the second, we see the body dead, but then he later becomes some kind of super zombie. And finally the third results in the death of the engineer, but the birth of the characteristic alien from the original movies.

How it might work.

Clearly, inside these eggs is the ability to transform a host organism into a monster via a couple different mechanisms. What this basically sounds like is a virus. Except viruses big enough to see with the naked eye have not really been discovered, though we don’t know if one of those black egg things are one unit of virus or maybe a big bag of them. Additionally, this virus is potentially one of the most sophisticated viruses, so perhaps it needs to be big. Regardless here’s my schematic for how I think the process works:

1. A creature must be infected.

a. via – ingestion, sexual contact, attack
b. Can be transmitted straight from the eggs/virus, or from host to host.
c. Sexual contact can transmit the virus to mother, but not actually infect her, instead opting to become an embryo in her womb.

2. The egg/virus DNA then takes over the host DNA.

a. This is the viral life cycle, a virus injects its DNA into a cell, forces the cell to use that DNA to make more virus, then destroys the cell to release more virus.
b. Though it may seem like the virus should be self-sufficient, in this case and in the case of real viruses, a host is required to provide nutrients.

3. A novel creature forms.

a. One option is for the entire body to completely disintegrate, and creatures to form from what remains. (Humans would be an example of this)
b. Another is for the formation of a monster/zombie.
c. Lastly a monster forms within the body of the host.

So the technology seems to require viral DNA and a host for the viral DNA to take over, or absorb nutrients to create a new creature.

Some issues.

The main issue I want to discuss is really how DNA is perceived. The writers did a good job of really creating a complete story around this technology, and the way they illustrated DNA is really quite exquisite, but how they described their process was a little suspicious sounding.

The writer says things like “DNA getting infected” a couple times, and they ultimately choose to illustrate it as the engineer’s beige DNA turning black to mean it has become infected. Unfortunately, this just shows what a foreign concept DNA is to many people. DNA isn’t some kind of liquid one poisons, or a cloth you can spill wine on. It is a macromolecule (meaning a molecule that is made up of molecular units called monomers) that has information coded into it based on the sequence of molecules. If something were to “infect” it, it would have to either physically break the molecule apart and add things to it (which is how viruses many times work), or it would have to actually change the molecules into other things to scramble the message (which is how mutagens such as UV rays and carcinogens work). If either of these mechanisms were the case, they both require something of the virus to interact with the DNA, either viral DNA coming in and adding itself, or some kind of protein or other chemical messing up the bonds in the DNA. (I doubt UV rays or another kind of energy could be contained in the eggs and cause such specific kinds of mutations.)

But perhaps my analysis is incorrect then, and the technology is not viral, but instead biochemical; so instead of viral DNA inserting itself into the host genome, the eggs instead mutate the host genome in a specific way to create the beast. This would require the black eggs to have encoded in its genome, genes that make incredibly sophisticated proteins that can specifically bind certain sequences of the host’s genome, and mutate it in a specific way to create the monsters. This could actually work quite well as a mechanism. And if this were the mechanism the writers were going for, then the way they illustrated the infection, from an abstract point of view, is not necessarily the worst, though you should remember that this kind of mutation would require some kind of protein or chemical interacting with the DNA.

But another strange issue with how they illustrated the process is showing the DNA disintegrate, and then come back together spontaneously and form cells around it. I can not honestly think of a way for this to really work without taking an incredibly long amount of time. Especially for cells to form de novo, or more simply put, from raw materials. Additionally, if the DNA actually does disintegrate, then all information should be lost, regardless if the eggs use viral DNA, or scramble the information by mutagenesis.

Some thoughts.

Though our understanding of proteins and their structure get better with every passing day, we are not yet at the sophistication to be able to create proteins that can specifically mutate specific sequences in a specific way to create something different. And we know a whole lot about viruses, their mechanisms, and their history, but we are far from being able to create a virus with the information capacity to make huge organismal changes like this.

But could you imaging the applications of these kinds of technology? We could create proteins that could specifically target a site in the genome and change it to something different. This would revolutionize medicine. People with genetic disorders could be cured as an embryo and literally never even have the possibility of passing the disorder to their children. It would wild!