Archive for August, 2011


There’s no gene for stopping bullets.

Wednesday, 24 August, 2011

There’s been a bit of talk recently about the bio-artist who managed to create a fabric of human skin and spider silk that managed to stop a .22 calibre round. Unfortunately the bullet didn’t ricochet off the skin, Superman-style. This skin acts a bit like a net stopping a soccer ball, in that it simply catches the bullet. Now imagine you kick the ball with superhuman strength into the net of soccer goal. If the net can’t stop the ball, one or both of two things will happen: either the net will break leaving a hole where the ball went through or the net will just tear right off the goalposts and both net and ball will keep sailing by.

In the case of this bulletproof skin/fabric, the skin wasn’t broken by the bullet. Instead, the bullet (now wrapped in spider silk and skin) still penetrated a couple of inches into the ballistics gel behind it.

For a visual, watch the video below (specifically the frame at 7:48).

Note that a Petri-dish sized piece of fabric was attached (through indeterminate means) to the ballistics gel. So as the bullet hits the middle of this circle of fabric, it pulls taut and in the case of the spider silk fabric, pulls off completely and envelopes the bullet. To go back to the soccer goal analogy, you can have a really strong net but if it’s poorly attached to the goalposts, it won’t stop a really fast ball. So while it’s possible that the tensile strength of the spider silk is enough that, if the fastening held, the bullet would be stopped completely, it is also possible that the skin would have broken had the fastening not broken first. More tests are needed, of course.

But anyway, if that gel was your heart, you’d still be very dead. So despite claims that the skin was ‘bulletproof’, the skin didn’t even stop a .22 bullet travelling at reduced speed. To be classified as a Type I vest (the lowest class of ballistic vest), the skin would have to completely stop a full velocity .22 round.

So, it’s not even bulletproof. And, it is just spider silk fabric covered in skin, it’s not really skin either. And so of course the press reports that bulletproof skin has been created and we transhumanists can rejoice at the promise of invulnerability.

That bastion of great reporting, The Daily Mail, quotes Dutch bio-artist Jalila Essaidi as saying:

“Now, let’s take this one step further, why bother with a vest: imagine replacing keratin, the protein responsible for the toughness of the human skin, with this spidersilk protein. This is possible by adding the silk producing genes of a spider to the gnome[sic] of a human: creating a bulletproof human. Science-fiction? Maybe, but we can get a feeling of what this transhumanistic idea would be like by letting a bulletproof matrix of spidersilk merge with an in vitro human skin.”

Yes, they said gnome. I lolled. But anyway, why would we bother with a vest? I don’t know, the fact that it actually works might be one reason. Or that it can be much tougher without having to also be nice and supple enough to allow you to move like skin does. And we can trade up to the newer models without having to have a new skin transplant or more genetic modification. The only disadvantage of a vest is not being bulletproof all the time.

Still, it’s kind of cool to have bio-artists out in the world experimenting with weird and wacky ideas like bulletproof skin, while all the ‘real’ doctors and scientists are trying to find ways to heal people with severe burns or gunshot wounds. Then again, it doesn’t mean much if the research is poorly tested and demonstrated on YouTube instead of at a scientific conference.

So will it ever be possible to have bulletproof skin? Probably not.

You see, our skin is flexible and can stretch pretty easily. If it didn’t stretch, we’d to moult and grow a new skin as we grow, get pregnant or gain weight. Also, we’d find movement difficult too (as anyone who has tried to squat in a pair of skin-tight jeans knows). Skin has to be this flexible even if we make it strong enough to stop a bullet. So despite a bullet not actually penetrating the skin, the skin will rapidly deform allowing the impact to cause severe underlying trauma, fracture bones or injure vital organs. (This happens with any soft body armour, and is called ‘behind armour blunt trauma’ or BABT). So although stronger, bulletproof skin might prevent penetrating injuries (and yes, save lives), bullets will still be potentially lethal. Bullet resistant skin? Possible. Nigh invulnerability thanks to bulletproof skin? Highly unlikely.

Or at least, it won’t look like skin. An hard exoskeleton like a crab, perhaps. But if we’re going for exoskeletons, I think Iron Man’s looks like a better option.

(And I know I totally glossed over the part where the spider silk was produced from the milk of a transgenic goat, but that’s because it’s 11-year-old news.)