Would a monkey be better or worse off with a brain made of human neurons? What if the result conferred to the monkey the ability to speak or exercise advanced learning? Would the goal be to create a new sub-human species designed for menial tasks, high-risk jobs or test subjects for experimental drugs and medical procedures?

Mixing the cells, organs and body parts of different animals or animals with humans is to create what are called hybrids or chimeras. This science is intimately related to transgenics – inserting genes from one species into another. These transgenic animals, also called bioreactors, allow gene function to be tested in a whole animal, rather than merely in a test tube or cell.

Research like this is considered the most powerful technology for modeling disease processes, revealing the secrets of human biology and understanding fetal development. It is also one of the many unrestrained directions of embryonic stem-cell research embraced by its proponents and making the news this holiday season.

The potential power of embryonic stem-cell research came to light only a few short years ago, while the potential power of chimeras came to light more than ten years ago when small sections of brain from developing quails were transplanted into the developing brains of chickens. The resulting chickens exhibited vocal trills and head bobs unique to quails. This proved that the neural circuitry and complex behaviors could be transferred from one species to another. Now the potential power of embryonic stem-cell research and chimeras are combining for some eyebrow-raising possibilities.

In recent experiments,scientists have created human-pig chimeras by adding human blood-forming stem cells to pig fetuses. (This creates pigs with human blood running through their veins that might be useful for transfusion.) They have also created human-sheep chimeras by creating sheep whose livers are up to 80 percent human. (Humanizing the livers of sheep is to make them more available to people who need transplants.)

Another line of experiments has produced a mouse with a nearly complete human immune system useful in testing drugs against the AIDS virus. And now scientists are injecting human neural stem cells into mouse fetuses, creating mice whose brains are about 1 percent human. The reports are that these mice “have learned things they never would have learned had there been a bioethical ban” on such experiments.

Obviously, one current trend is to insert more and more human DNA into an animal of another species. So the question is whether or not there should be a limit to the amount of human DNA or cellular material shared between a human and an animal.

At present, there are no federal guidelines or controlling recommendations. There appears only the moral conscience of the scientists conducting the experiments themselves. But few researchers can agree on even the most basic dos and don’ts of this runaway train of technology.

So where do we look for guidance? A time-tested standard is none other than the Bible.

The Bible tells us that God designed procreation so that plants, animals and humans always reproduce after their own kind. That means species integrity is defined by God, rather than by arbitrary or evolutionary forces. The Bible also tells us that bestiality (sex between humans and animals) violates the sacredness of human life created in the image of God and is punishable by death.

According to Dr. Nancy Jones, of Wake Forest University School of Medicine, “closer examination of the Bible suggests that Scripture is concerned with more than just the physical defilement associated with sex between a human and an animal. Leviticus 18:23 ends with the phrase ‘it is confusion.’ The word confusion (tebel) means ‘in violation of nature or divine order.’

“Of course, the distinction between physical copulation and the creation of offspring becomes important in transgenic and chimeric technology involving animals and humans – because while no physical copulation occurs, the resulting offspring have genetic material from different species.”

So at what point has science and medicine crossed the line? Does inserting an insulin gene from a pig into a human being, whose own genes for insulin production are defective, violate divine order? Are people whose defective heart valves are replaced with those from cows technically hybrids or chimeras? And at what point do we recognize that significant aspects of humanity have been conferred to animals?

Regardless of the answers to these questions, it is critical to keep in mind where unrestrained research like this is headed. Fact: The ultimate goal of every animal experiment is its eventual application to humans.

This is often accomplished through function creep – that is where a product or a technology is created for a particular purpose that all agree is good in order to obtain public acceptance. Then comes the nefarious after-market with its unintended but more often publicly unanticipated uses.

So, while no one is yet to add the genes of monkeys to men, it is easy to foresee future justifications for just such experiments. Consider that monkeys don’t contract AIDS. What if it were possible to transfer this immune resistance to humans? Would that be reason enough for creating part man-part monkey chimera? Welcome to the very real “Island of Dr. Moreau.”

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