Fun with pig clones

Every porker is different, even if it shares the same genes with a litter of siblings. So forget about ordering a copy of your favorite faithful companion.

Topics:

In the early weeks of 2003, apparitions of Raelian-cloned babies have haunted headlines.

But the Raelian cult, whose members believe that the human race is descended from aliens, has failed to offer any proof that it has in fact bred the first human clone.

Until the cult comes up with some proof, nine red pigs in Texas have more to teach us about cloning than all the Raelian press conferences combined.

In an article forthcoming in the scientific journal Applied Animal Behaviour Science, Greg Archer, a graduate student in the animal science department at Texas A&M University, and Ted Friend, a professor there, detail the results of their behavioral study on the cloned pigs, born in two different litters.

Although all the pigs were cloned from the same fetal pig’s cells, studies found that the pigs have distinct personalities, much like any other litter. The finding goes against the sci-fi conceit that cloned droids would not only look alike, but behave like carbon copies of each other.

Ted Friend, Ph.D., an expert in animal behavior, spoke with Salon by phone from his office in College Station, Texas.

What was the purpose of your cloned pig experiment?

It was to look at the variation among cloned animals to see how similar they are to each other from a behavioral standpoint. The issue was: Do they have individual personalities or not? Do they act like little Homer Simpsons?

Homer Simpsons? What do you mean?

I just saw the episode of “The Simpsons” where Homer got himself cloned about 30 million times.

And all the Homers were identical?

Yes, of course, and they all had a craving for jelly doughnuts. That’s how they got rid of all the clones that were running over Springfield. They took a bunch of jelly doughnuts and tied them on the bottom of a helicopter and flew out over a cliff, and all the clones ran off the cliff looking for the doughnuts.

[But] most people in biology would suspect that they’re not going to be identical at all.

Why?

Environmental influences. When you clone, you’re starting off with a very young animal. So, it won’t have the experiences that an adult had.



It won’t have the formative jelly-doughnut experience?

Right.

Plus, there may be other things going on in the genetics. Scientists working in cloning call this the “epigenetic effect.” When some of these genes are expressed, there’s a lot of variation.

Even amid clones of the same organism, their genes are going to be expressed differently?

They might be. Right. Everything that we see from these pigs says yes.

How did you study the cloned pigs?

We looked at their behavior. We ran a bunch of tests used to assess temperament in animals. One series tested how they respond to restraint.

People do something like this very often when they’re at a shelter adopting a dog, and they want to get a guess what the dog is like. They hold the animal on its back, and see if it struggles a lot. We did that with these pigs. Also, hold them down. Pick them up to see how many times they’d fight or argue or oink. Measure that.

Also, putting a blanket on their heads, which is a standard one. Put a blanket over a dog’s head, and see if takes it off right away or if it sort of stands there. There was a lot of variation within a litter of cloned pigs. One pig would shake the blanket off immediately, and do that repeatedly. And another pig would just sort of sit there with the blanket on its head.

So, one pig was feisty, and one was complacent?

There were very different personalities in all the pigs, which is typical of pigs. One liked to play with people, and one didn’t. One clone really liked to play with my 11-year-old son, just romp all over the pasture with him, and chase him like a little dog would. And the other pigs didn’t want anything to do with him.

We did other trials, too — food preference. That showed a lot of variation. Some would eat one particular type of food that some others wouldn’t want anything to do with, and it was all fairly similar to what you’d see in a typical population of pigs.

So, even though they are genetically identical they behave as if they were just litter mates?

Right.

So, this suggests that the hope that people have that if their dog dies, and then they have it cloned, it’s going to be their same dog, is just a fantasy.

There’s no basis for that all. If I clone Elvis, will he come back and sing? Probably not. He probably won’t even have Elvis’ hips.

How did you structure the study?

It was run with two litters, one litter of five, and one litter of four cloned pigs. These were durocs, which is a red breed of pig.

All the pigs were genetically identical. They were all from the same cell, originally. They were born in the fall of 2001.

Why did you decide to clone durocs in particular?

The surrogate mothers who would carry them are white pigs. If the white sow had anything that was red, you’d know it was a clone. You couldn’t possibly get it mixed up with something else.

Why did you need two different litters? You wanted more pigs?

A litter offers you a very useful kind of comparison, because you have multiple clones from the same animal. If someone was cloning sheep, you’d usually have one clone from each ewe, from each mother, and that meant you’d have five different mothers.

And then you get into the issue of how much effect does the mother have, whether the mother is flighty or nuts. The environment not only includes after the animal is born, but also the environment in utero when the embryo is developing, and the factors when the embryo is developing can have a profound effect on their behavior as well, as adults or on their personalities later on. Because neural circuits and hormonal patternings are being established as an embryo.

What do you think that the implications of this are for the nature vs. nurture debate? Doesn’t it imply that a lot of personality is environmental?

Well, environmental, but there’s more than just what the animal experiences. A lot of this is epigenetics, which is different things influencing how these genes are expressed. There’s very little known about it at this time.

It’s not so much necessarily environment. I think a lot of the individual pig’s personality is set when he’s born, like a lot of people. Certainly environment influences it, but if you’re going to be aggressive or outgoing or whatever, a lot of that is kind of set.

Can you say more about this issue of the same genes being expressed differently?

There is a lot of variation, things going on that we don’t know about. How they’re replicated can make a difference, and there are some manipulations going on in the genes, while they’re doing the transfer. We see some things that imply that there’s normal variation in the genes as they’re replicated.

It’s different from identical twins. It’s a very different situation than when you’re dealing with identical twins.

How so?

Well, with identical twins you’re splitting an embryo, you have one original embryo, and it’s sort of split into two. And here you’re dealing with individual embryos, each one separate at the initial stage of replication.

There’s another issue, too, if you’re trying to clone your dog. When you talk about identical twins, you have two people who look the same and behave fairly similarly, well, those two people grew up together, too. And they developed from a young cell vs. an old cell, and in cloning, if you’re trying to clone your dog, then you’d be using old cells or mature cells.

Oh, I see. The identical twins grew up together, whereas the clone of your dog didn’t grow up in the same environment as your dog.

They may have a different mother, but still there’s a lot of manipulations done to the genes, and that can influence how they’re expressed. But this is something that everyone is just looking into now, so there’s very little known about it at this point.

What are the cloned pigs doing now? Are you still studying them?

Not much. Most of them farrowed. They were all females. They’ve been re-bred. They’ve had babies of their own.

Have the pigs had any health problems? You know, people often talk about how Dolly, the sheep, and other cloned animals have health problems.

Well, she was an old cell, and we’re dealing with young cells, since these pigs were cloned from fetal cells. Fetal cells are usually easier to work with and you usually have fewer problems than if you’re dealing with adult cells from the mature animal.

Because you’ve taken the old cell, and you’re trying to “reprogram” it, is the term, to get it start growing as a baby again. That’s difficult.

Like in the case of somebody trying to clone their pet.

Right. And that’s where you get a lot more problems. When you’re dealing with a fetal cell already, that’s programmed to say: “Hey, I’m a baby. Let’s grow.” You have fewer problems, usually no problems. Our cloned pigs have had no problems that I’m aware of that we’ve ever seen that’s different from normal pigs.

What did you make of the Raelians’ announcement that they’d cloned a human?

As a researcher, I guess I’d have to say that I don’t know. They gave no evidence, no nothing. It’s just one person up there. Maybe it’s a shame the press and the media made as much out of as they did without more information.

Why are you laughing?

Oh, let’s not go there.

More Related Stories

Featured Slide Shows

  • Share on Twitter
  • Share on Facebook
  • 1 of 11
  • Close
  • Fullscreen
  • Thumbnails

    Ten spectacular graphic novels from 2014

    Beautiful Darkness by Fabien Vehlmann & Kerascoët
    Kerascoët's lovely, delicate pen-and-watercolor art -- all intricate botanicals, big eyes and flowing hair -- gives this fairy story a deceptively pretty finish. You find out quickly, however, that these are the heartless and heedless fairies of folk legend, not the sentimental sprites beloved by the Victorians and Disney fans. A host of tiny hominid creatures must learn to survive in the forest after fleeing their former home -- a little girl who lies dead in the woods. The main character, Aurora, tries to organize the group into a community, but most of her cohort is too capricious, lazy and selfish to participate for long. There's no real moral to this story, which is refreshing in itself, beyond the perpetual lessons that life is hard and you have to be careful whom you trust. Never has ugly truth been given a prettier face.

    Ten spectacular graphic novels from 2014

    Climate Changed: A Personal Journey Through the Science by Philippe Squarzoni
    Squarzoni is a French cartoonist who makes nonfiction graphic novels about contemporary issues and politics. While finishing up a book about France under Jacques Chirac, he realized that when it came to environmental policy, he didn't know what he was talking about. "Climate Changed" is the result of his efforts to understand what has been happening to the planet, a striking combination of memoir and data that ruminates on a notoriously elusive, difficult and even imponderable subject. Panels of talking heads dispensing information (or Squarzoni discussing the issues with his partner) are juxtaposed with detailed and meticulous yet lyrical scenes from the author's childhood, the countryside where he takes a holiday and a visit to New York. He uses his own unreachable past as a way to grasp the imminent transformation of the Earth. The result is both enlightening and unexpectedly moving.

    Ten spectacular graphic novels from 2014

    Here by Richard McGuire
    A six-page version of this innovative work by a regular contributor to the New Yorker first appeared in RAW magazine 25 years ago. Each two-page spread depicts a single place, sometimes occupied by a corner of a room, over the course of 4 billion years. The oldest image is a blur of pink and purple gases; others depict hazmat-suited explorers from 300 years in the future. Inset images show the changing decor and inhabitants of the house throughout its existence: family photos, quarrels, kids in Halloween costumes, a woman reading a book, a cat walking across the floor. The cumulative effect is serene and ravishing, an intimation of the immensity of time and the wonder embodied in the humblest things.

    Ten spectacular graphic novels from 2014

    Kill My Mother by Jules Feiffer
    The legendary Pulitzer Prize-winning cartoonist delivers his debut graphic novel at 85, a deliriously over-the-top blend of classic movie noir and melodrama that roams from chiaroscuro Bay City to Hollywood to a USO gig in the Pacific theater of World War II. There's a burnt-out drunk of a private eye, but the story is soon commandeered by a multigenerational collection of ferocious women, including a mysterious chanteuse who never speaks, a radio comedy writer who makes a childhood friend the butt of a hit series and a ruthless dame intent on making her whiny coward of a husband into a star. There are disguises, musical numbers and plenty of gunfights, but the drawing is the main attraction. Nobody convey's bodies in motion more thrillingly than Feiffer, whether they're dancing, running or duking it out. The kid has promise.

    Ten spectacular graphic novels from 2014

    The Motherless Oven by Rob Davis
    This is a weird one, but in the nervy surreal way that word-playful novels like "A Clockwork Orange" or "Ulysses" are weird. The main character, a teenage schoolboy named Scarper Lee, lives in a world where it rains knives and people make their own parents, contraptions that can be anything from a tiny figurine stashable in a pocket to biomorphic boiler-like entities that seem to have escaped from Dr. Seuss' nightmares. Their homes are crammed with gadgets they call gods and instead of TV they watch a hulu-hoop-size wheel of repeating images that changes with the day of the week. They also know their own "death day," and Scarper's is coming up fast. Maybe that's why he runs off with the new girl at school, a real troublemaker, and the obscurely dysfunctional Castro, whose mother is a cageful of talking parakeets. A solid towline of teenage angst holds this manically inventive vision together, and proves that some graphic novels can rival the text-only kind at their own game.

    Ten spectacular graphic novels from 2014

    NOBROW 9: It's Oh So Quiet
    For each issue, the anthology magazine put out by this adventurous U.K.-based publisher of independent graphic design, illustration and comics gives 45 artists a four-color palette and a theme. In the ninth issue, the theme is silence, and the results are magnificent and full of surprises. The comics, each told in images only, range from atmospheric to trippy to jokey to melancholy to epic to creepy. But the two-page illustrations are even more powerful, even if it's not always easy to see how they pertain to the overall concept of silence. Well, except perhaps for the fact that so many of them left me utterly dumbstruck with visual delight.

    Ten spectacular graphic novels from 2014

    Over Easy by Mimi Pond
    When Pond was a broke art student in the 1970s, she took a job at a neighborhood breakfast spot in Oakland, a place with good food, splendid coffee and an endlessly entertaining crew of short-order cooks, waitresses, dishwashers and regular customers. This graphic memoir, influenced by the work of Pond's friend, Alison Bechdel, captures the funky ethos of the time, when hippies, punks and disco aficionados mingled in a Bay Area at the height of its eccentricity. The staff of the Imperial Cafe were forever swapping wisecracks and hopping in and out of each other's beds, which makes them more or less like every restaurant team in history. There's an intoxicating esprit de corps to a well-run everyday joint like the Imperial Cafe, and never has the delight in being part of it been more winningly portrayed.

    Ten spectacular graphic novels from 2014

    The Shadow Hero by Gene Luen Yang and Sonny Liew
    You don't have to be a superhero fan to be utterly charmed by Yang and Liew's revival of a little-known character created in the 1940s by the cartoonist Chu Hing. This version of the Green Turtle, however, is rich in characterization, comedy and luscious period detail from the Chinatown of "San Incendio" (a ringer for San Francisco). Hank, son of a mild-mannered grocer, would like to follow in his father's footsteps, but his restless mother (the book's best character and drawn with masterful nuance by Liew) has other ideas after her thrilling encounter with a superhero. Yang's story effortlessly folds pathos into humor without stooping to either slapstick or cheap "darkness." This is that rare tribute that far surpasses the thing it celebrates.

    Ten spectacular graphic novels from 2014

    Shoplifter by Michael Cho
    Corinna Park, former English major, works, unhappily, in a Toronto advertising agency. When the dissatisfaction of the past five years begins to oppress her, she lets off steam by pilfering magazines from a local convenience store. Cho's moody character study is as much about city life as it is about Corinna. He depicts her falling asleep in front of the TV in her condo, brooding on the subway, roaming the crowded streets after a budding romance goes awry. Like a great short story, this is a simple tale of a young woman figuring out how to get her life back, but if feels as if it contains so much of contemporary existence -- its comforts, its loneliness, its self-deceptions -- suspended in wintery amber.

    Ten spectacular graphic novels from 2014

    Through the Woods by Emily Carroll
    This collection of archetypal horror, fairy and ghost stories, all about young girls, comes lushly decked in Carroll's inky black, snowy white and blood-scarlet art. A young bride hears her predecessor's bones singing from under the floorboards, two friends make the mistake of pretending to summon the spirits of the dead, a family of orphaned siblings disappears one by one into the winter nights. Carroll's color-saturated images can be jagged, ornate and gruesome, but she also knows how to chill with absence, shadows and a single staring eye. Literary readers who cherish the work of Kelly Link or the late Angela Carter's collection, "The Bloody Chamber," will adore the violent beauty on these pages.

  • Recent Slide Shows

Comments

0 Comments

Comment Preview

Your name will appear as username ( settings | log out )

You may use these HTML tags and attributes: <a href=""> <b> <em> <strong> <i> <blockquote>