How bizarre Can Genetically Engineered Plants/Animals Be?

I am really excited by the prospect of genetic engineering…particularly the prospect that all kinds of monsters could be made! For example, suppose weneed an animal that can eat up aquatic plants (such as the chinese water chestnut plants that clog the Charles River). We simply indsert a cow gene into a manatee, and add a little polar bear (for cold-water capability)-presto! We now have a hardy herbivore that can operate in cold weather! Anybody remember that SIMPSONS episode where Bart gets mixed up with the fly!Are we likely to see such GM plants like a cross between crabgrass and corn, that makes alcohol?
The future isindeed bright!

One of the bizarrist plants I’ve seen is tobacco plants that have glo-worm genes in order to make them glow in the dark.

ralph, that Simpons episode was a parody of two earlier movies - both called The Fly, in which the main character slowly gets his body parts swapped with a fly’s.

How about a mouse that glows in the dark? Go here to see pictures and a movie: http://www.mshri.on.ca/nagy/

I have seen pictures of mice homozygous for the LIM1 knockout that are born without heads. I think it was published in Nature (1995, 374;425-430) but I cant find the paper right now to double check.

While current technology allows us to insert or delete genes in animals there is still a lot to learn about how an animal is formed. Currently we can’t just insert a cow gene and some polar bear genes into a manatee and know with any certainty what will result. But as we learn more about how genes interact to create the whole animal (or plant) this might become feasable.

John

And in the same vein, dont forget Alba, the fluorescent bunny!

What the heck is a “cow gene” or a “polar bear gene”, anyway? If you mean “a gene specific to the cow (or polar bear)”, then it would make a rather significant difference which specific gene (or genes) was transplanted, I would think.

As far as I understand it, DNA works something like this:

It consists of a long chain of molecules that encode the instructions for the manufacture of other complex molecules such as proteins and enzymes.

Once these other complex molecules have been constructed, they take part in a web of interaction, from which the growth and development of the organism is an emergent phenomenon.

So a certain gene might code for a certain molecule that is important in the web of interactions that ultimately produces, say, hair inside the ear, but the same molecule may also be involved in other webs of interaction, maybe another that ultimately bestows the organism with, I dunno, say, functional bone marrow (stupid hypothetical examples), so disabling a gene in order to prevent the unsightly growth of hair from the ears, may have the desired effect, but at the expense of killing the organism.

Anyway, chopping a chunk of cow genome out and inserting it into the genome of another organism (say a strawberry) won’t make beefberries, it will result in some cow proteins being produced suring development; depending on how these interact with the host’s natural development processes, the end result is difficult to predict.

If we had the computational power to model the chemical interactions at every level, we might actually be able to design organisms from scratch, but it is a horrendously complex problem.

This post was brought to you by the armchair college of genetics, if anyone suitably qualified wishes to slap me down, I have all four cheeks bared and ready.

Mangetout-

No slapping down necessary, that was a very nice analysis of the problem. However, progress is being made in the field. May I direct you to:

http://www-acs.ucsd.edu/~idea/wellsshrimp.htm

where they describe the insertion of a mutant Hox gene from a shrimp into a fruit fly, resulting in a fly with extra legs.
Now, the goal was not to create a fly that’s extra-capable of crawling on your ceiling, but rather to demonstrate that simple changes in single genes can result in mutations that MAY lead to evolutionary changes and/or speciation…which is pretty interesting in itself.
hehe…“Beefberries”…hehe

Hmmm…perhaps I should’ve looked over that website before posting a link to it. They’re an “intelligent design” group, a concept which I don’t prescribe to. Instead, go to:

http://ucsdnews.ucsd.edu/newsrel/science/mchox.htm
for a more scientific analysis of the study I mentioned.

The HOX genes in fruit flies have been studied a lot in this context. If edwino shows up, he can tell you more. They’re important early developmental genes that help determine which cells turn into which structures. Scientists have been fiddling with them for years to figure out how exactly they work. I’ve seen pictures of flies with legs where their eyes should be, among many other bizarre rearrangements.

But fruit flies are a lot easier to fiddle with than mammals.

I think the weirdest I’ve seen was the mouse with a human ear on its back. Ick. The glowing mouse is quite impressive, though.

An animal that can eat aquatic plants? Couldn’t most herbivores? Or fish, if you want an aquatic animal? The point being, that it has to be quite seriously weird before nature hasn’t already beaten us to it :smiley:

I suppose I should have added that I’m more than intimately familiar with the HOX genes myself- my doctoral thesis work was a study of the role of HOX genes in guiding hematopoiesis. I found that blocking the expression of one of the genes (HOXA5) resulted in stem cells that favor development of erythrocytes at the expense of macrophage/monocytes/granulocytes. So, these genes seem to have an important role in directing development of the organism during the embryonic stage and throughout it’s lifespan.

Shade, are you sure about the human ear story? As I recall, researchers had implanted an ear-shaped piece of plastic under the mouse’s skin, in order to {insert some practical purpose here}, which would make a more natural artificial ear for someone.

:smack: I seemed to recall a new scientist article or something but on google to http://www.madsci.org/posts/archives/jun2000/961007439.Ge.r.html it seems you’re right. Sorry about that. Still pretty weird, but not genetically engineered.

How about a fly with eyes all over its body. Can anyone find a cite (a qucik google failed)?

How about rodents designed to get Lou Gehrig’s disease? Reliably, predicatably, every time. Or fat-free zebra fish?

They’re here!

How long until I can get a poodle that poops gold?

How about reverse-engineering an electric eel, so you have an animal that “feeds” on electricity?

Or a “plant”- for want of a better word- that has organs that are the opposite of muscles: they convert motion into chemical energy. Grows in windy areas where it’s branches are constantly being swayed, and can grow even in permanently sub-freezing environments like the polar icecaps.

A big question is whether animals could be engineered to grow materials not found in nature, like diamond-coated teeth and graphite-composite bones.

Flies with eyes all over its body? I can provide them by the hundreds in two weeks. Just cross dpp-GAL4 and UAS-ey, which I have in bottles right now and I can collect by the dozens.

stochastic – nice to see another developmental geneticist around here. I’m working on a PhD in fly eye development.

About HOX genes: they can only be thought of as light switches. Without the light, the socket, the wiring, and the electricity (the developmental pathway genes), nothing happens when I flip the switch. The HOX (homeotic box) binds DNA to activate it – it has no magical properties by itself. Some HOX genes give spectacular phenotypes, some are pretty mundane taken by themselves. They tend to sit near the tops of pathways, but there are lots of pathways which are redundant or which control minor aspects of development (the third antennal segment or the fourth cervical vertebra, for instance).

ey, which stands for eyeless, is a HOX gene in fruit flies (actually its HOX domain is disposable for eye development, but we won’t go into that now…) It activates a network of genes which tells a field of undifferentiated cells that it is a retina. Once this is determined, other gene cascades to tell cells to become photoreceptors, pigment cells, bristle cells, and lens secreting cells. Obviously once a cell knows it is a photoreceptor, more genes like rhodopsins and ion channels are produced. Without this machinery, ey does nothing.

We can make all kinds of bizarre twists by manipulating HOX genes and other master control genes in flies. We can transpose antennae and legs. We can duplicate entire body segments, including ones in the thorax which cause a double pair of wings. And we can grow eyes on the legs, antennae, and wings. There are a whole host of scary mutants when we are talking about perturbing or manipulating pathways within one organism.

We have some examples already presented of freaky mutations between species: the fly with extra legs. This is due to evolution in the Arthropoda of another HOX complex which controls body layout (and is the one which causes a double set of wings – the Ultrabithorax or Ubx complex). In flies, Ubx has a repressive domain which apparently restricts leg induction to the thorax and not the abdomen. The shrimp one does not have that domain, and replacement of fly Ubx with shrimp Ubx causes leg induction into the abdomen.

Nearly every other example is one or perhaps two genes introduced into another animal – Green Fluorescent Protein is put into everything nowadays, cytokine receptors to give mice susceptibility to HIV infection, bt in tomatoes to allow for cold resistance. We are not very sophisticated yet. The next step, something like making a mouse which grows chicken feathers, is still years and years away. We would need to first understand every step of feather formation, every gene involved, their expression patterns and levels, their degradation patterns and posttranslational modifications, and the proper cellular environment for this to happen. I’m sure a significant proportion of a chicken’s genes (and regulatory regions) are involved in this. Sure, some can be substituted by mouse copies of the chicken genes, but it is still a helluva lot to know. We are nowhere close. Even something as simple as bacterially produced spiderwebs or cotton is proving tough, as the toxicity and specific cellular excretion of the proteins is a major factor which has not been fully understood.

[Tim the Enchanter]
That’s ne ordinry rabbit!
[/Tim the Enchanter]

I want a florescent bunny rabbit!

Genetic engineering, look at the wide range of variation that breeders have been able to introduce into ordinary dogs and cats. There was a NOVA ep on dogs once that said all dogs were bred from something that was a lot like your typical mutt – short hair, about half a meter at the shoulder, curly tail. My suspicion is that we’ll have some pretty wild stuff coming down the pike over the years, and in a century or so things will probably be as different due to genetic engineering as they are now prior to the introduciton of electricity and modern media.