I know I should probably let dead dogs lie but some of the comments about biology and what’s feasible got me thinking.
So here’s what we know about biology and genetics that could affect something like the wulfen curse.
Fact: About every seventh year the human body will have replaced practically every cell in its body.
Fact: This is in a perfect mechanism. Damages to a cell’s DNA often cause errors to appear in the process or otherwise known as mutation. Most often these mutations lead to rapid and abnormal growth of the cells. We know it as cancer.
Fact: RNA viruses exploit this mechanism of cell-division by replacing parts of the cell’s DNA with its own RNA forcing the cell to produce new viruses. This is the cause behind some of the most horrific and lethal diseases on the planet such as Ebola or AIDS.
Fact: Geneticists can use modified RNA viruses to program a cell’s DNA with new DNA strands of their choice. This is how we have corn that can survive in cold climates or how mice can grow a human ear on their backs. For example, corn gets parts of its DNA replaced with DNA from cold resistant fishes making them able to survive cold temperatures.
Fact: By combining the ability to reprogram DNA with RNA viruses with the fact that the human body is always replacing old cells with new, scientists have come up with something called gene replacement therapy. This a medical procedure that tries to cure genetic diseases by reprograming the flawed cells that causes the disease so that when the flawed cell is reproduce the new cell will be a healthy cell whose DNA no longer carries the errors that cause the flawed cells and the disease in the first place.
But the cure only works at the pace of the human body’s own cell reproduction rate.
Now so far all I’ve talked about is real life science. This is what geneticist does in labs right now. Want to know more. Then just check out Wikipedia or take a subscription to Science or Nature.
However, let’s look at space marines and 40k universe.
Now we know from codexes and IA articles that when a human is made into a space marine huge physical changes takes place in his body. For example his bones grow longer and denser (which btw from a biological point of view isn’t as smart as it sounds) and his ribcage fuses into a single thick bone plate.
We also know that these processes take time, often over ten years. It isn’t an instant process but a natural process taking advantage of the body’s own regenerative mechanism such as cell reproduction.
We also know that a space marine candidate have to be young to be turned into a space marine as the process takes advantage of the human body’s growth from a child into an adult.
And that all this is triggered by the introduction of geneseed into the candidate.
If we combine what the fluff tells us about the making of a space marine and what genetics tells us, I think that we can safely conclude that what geneseed really is glands producing RNA viruses that are used to reprogram the human cells into becoming space marine cells.
Now let’s examine the curse of the wulfen. We know that the Space Wolves’ geneseed was created using canine strands of DNA. We also know that their geneseed is unstable so that if the candidate isn’t strong enough he will transform into a half man, half beast creature known as a wulfen.
From what we know it would seem likely what’s really happening is that the geneseed instead of creating superhuman space marine cells reinforced by positive canine abilities the geneseed is instead simply replacing the human cells with something resembling canine cells (or more likely dog/human hybrids) creating the half human half beast that is a wulfen.
However, would that process be able to change a human into a wolf thus fulfilling the there are no wolves on Fenris comment?
Theoretically, yes. If you can replace all the human cells in a body with super human space marine cells there is nothing that prevents you from replacing the human cells that transforms a being into a body of a wolf.
Note however and this important, we’re talking about transforming a human body into a body identically of that of wolves. Not changing a human into a wolf. You can’t change species but you could however change physical features.
Such a transformed wolf would not be a Canis Lupus but a **** Sapiens Lupus.
Of course, while you could theoretically change a human body into that of a wolf through some process resembling gene replacement therapy the transition period would always kill the subject as no organism could survive consisting of cells from two different types of organisms at the same time.
(Fine, lichens but then lichens is a cellular level symbiotic relationship between an algae and a fungus let’s just simplify things by saying it’s two different organisms living in one body.)
So neither wulfen or fenrisian wolves should survive the curse.
Unless there is some additional mechanism involved that we don’t know about that keeps the subject alive and seeing how much more advanced science in the 40k universe are compared to our own that a safe assumption to make.
Which means that with a little faith in Big E (or some long forgotten noble laureate) biology do indeed allow for a space marine to transform into a wolf.
And we haven’t even mention psyker magic or warp mutations. This is all science and conjectures drawn from predictions on how the scientific field will progress. (Gene replacement therapy will probably been perfected within the next hundred years tops. So real life space marines are probably only a couple of hundred years away, not forty thousand.) Throw psyker magic and the warp into the mix and who knows what’s possible.