Dear FRONTLINE,

Instead of killing a pregnant pig to retrieve cells to implant into humans, why not use cells from aborted human fetuses?

It's estimated that there are around 1,365,730 legal abortions performed annually in the United States -- more than 38 million since 1973. Given that these abortions are performed voluntarily, it is far more ethical than abusing defenseless animals.

And it wouldn't involve the astronomical risks and probable chance of failure associated with xenotransplantation.

pensacola, fl

Dear FRONTLINE,

I say we should drive on ahead and fund more research for programs like this. I hear so many people saying "Why are they messing with that, they shouldn't play God" - well some think that way until they are on the waiting list for organs or Godforbid their children then its take out all the stops.

Progress needs to be made - save some peoples lives - Risks are a part of living and a part of dying you take a risk either way, the risk of doing research and discovering or the risk of missing an opportunity because the chance wasn't grasped.

Experimentation and research into transplants like this need to continue and at a fevered pace before more people die.

Doug Abele
apopka, florida

Dear FRONTLINE,

I too watched the program in utter fascination. There is somethig about transplanting animal organs into humans that is just wrong. Plain wrong. I am for animal research, but I think we would be better served to come up with artificial devices to replace defective organs.

I have a question, the animal rights people that are angry about the fetal pig research (cutting off the pig's head), are they just as angry at human fetal research?

Tony Smith
west memphis, ar

Dear FRONTLINE,

It is a very difficult issue. I am inclined to be pro-animal rights, but then I think of a friend of mine who had a kidney transplant. If no human donor had been available, and a pig transplant could have saved her life, of course she is more important than a pig, or a dozen pigs, or a hundred pigs. But if more than 10,000 pigs and hundreds of primates have died, and we still haven't made xenotransplantation work, was it worth it? I can't say yes. Thank you for an important and provocative program.

minneapolis, mn

Dear FRONTLINE,

I watched your show in utter horror and was sickened by what I saw. First a baby has a baboons heart transplanted into her and proceeeds to die. Then we proceed to kill intelligent animals by trying to implant a pigs heart into them, just to watch them die by the hundreds. If the baby rejects a baboons heart, why would a baboon accepet a pigs heart? Oviously it can't.

It would seem in this day and age that a simple blood test could show that incompatibilties exist that will lead to organ rejection. If not then develop one. Until such a test shows positive results, experiments that lead to the wrongful death of animals should be stopped.

Rudi Mallant
monroe, wa

Dear FRONTLINE,

I thought your story regarding using animals organs for a substitute for human organs was verrry interesting. One can not say what they would never do, especially in a life and death situation.

However, the implanting of human DNA in animals (pigs) I thought was high-tech beastology. I can not see any reason to perform such an experiment. Please keep up the excellent work.

Rozi Horn
aurora, co

Dear FRONTLINE,

I have mixed feelings about this. I care about animals but if this research can bring treatments that can restore human life and cure diseases, I can't be against animal research.

Your program got me angry, you elaborate to the extreme with the animal research procedures, then you breeze through the end results. The young woman who had the stroke showed improvement with speech, clear eyes, responding to the few questions asked with enthusiasm and clarity.

I have approximately 10% usage of my body. Pig stem cell transplant or human stem cell transplant will be my treatment when all these negative attitudes realize that this type of Cell research will continue. It is too promising not to.

RenČ Bettencourt
capitola, california

Dear FRONTLINE,

I was up late last night to see this program. Although some of the images were hard to see, I also see the point of the research. It's not that animals don't have rights, but they don't have kids depending on them for 18+ years. They don't have bills left behind upon demise. They don't have loved ones holding their hands in hospitals being begged to fight harder.

If you have ever loved or lost anyone who was sitting on a transplant waiting list, you know the pain. Children left behind with painfull questions never answered. Parents wondering what they did wrong. Stroke VICTIMS left with less than half the life they had yesterday! I understand that an animal is equal born in nature or made in a lab. But sad as it may be, born in a lab, they truly don't know what their life could be missing. One day, the pig in the labs may save YOUR baby born with only this chance of a normal life. Keep that in mind as you bash the science of the 21st century.

Shonna Washburn
rio rancho, nm

Dear FRONTLINE,

My seven year old daughter is going to die without a heart/double lung transplant. I sadly admit, that I too believed in my heart years ago, that what constituted being unecessary and deplorable research on animals now becomes my prayer...to find hope that my daughter might live! Like one viewer wrote, it could be you tomorrow.

Andrea Goforth
central point, or

Dear FRONTLINE,

...Animal experimentation has been a part of the field of medicine from its beginnings. I have no reason be believe that scientists needlessly kill animals. Bearing in mind that each trial and each subject costs money and time in a race to save human lives, scientists, it would seem, are trying not to kill any of their subject animals. To breed a pig in a super-sterile environment seems awkward to say the least. Then again, many of the animals we eat as food are bred in much less hospitable conditions. Whereas these animals are raised for the sake of being killed to feed some people one meal, the pigs of organ farms are bred to save the lives of several humans. Indeed, there should be research on other methods of organ creation. These methods include stem cell research among others. However, none of these methods are without their detractors. Controversy follows science, but for all the animal experimentation in the past, we have been able to develop drugs to treat numberous diseases. Medicine is a fascinating, albeit confusing science. I fully understand the concerns of others regarding this new branch of medicine. However, I have faith that xenotransplantation research, such as the type FRONTLINE profiled, will yield results.

boston, massachusetts

Dear FRONTLINE,

Thank you Frontline for your well-balanced and informative program on xenotransplantation. I too was profoundly disturbed and echo the sentiments of most of the people who have expressed themselves so eloquently. I believe xenotransplantation is the wrong path to improving human health. It's too risky, too expensive, too inhumane and too bizzare.

We shouldn't be locked into the animal model. It's history is abysmal, although I realize the vested interests will fight hard to keep it alive. We need to pursue some of the more imaginative and enlightened alternatives. In vitro, like cloning and growing organs from an individual's own cells would be a better path for xenotransplantation. In light of all this, we humans need to reflect seriously on the path we are racing down as we unravel and meddle with millions and millions of years of evoluntionary life.

One of the people writing in reminded us that: "We do not stand at the apex of creation as humans with the mandate to control and subdue creation.' Ab-Seng Choo

Penelope Wells
anchorage, alaska

Dear FRONTLINE,

I am in need of a liver. I understand that I will more than likely die BEFORE I get one. At this time I am not quite bad enough for the list. My quality of life is not what it used to be, but there are so many more out there worse than me. My doctor said five years ago I would already be on the list and moving up. This goes to show that the demnd is much greater than most of us understand. My own thoughts on the matter are that may be we should spend a little more time and money on educating the public on donating. If you wait till the time of death it is to late. Families are greaving and donation is the last thing on their mind. I myself think it might be hard to donate my childrens organs but I know it is necessary for others to live. One thing that must not be forgotten is that we are all entitled to our own belifes and others must respect this. If someone chose not to donate then I must respect this and hope they are never in need of this type of help. We need to help and get along this might change the way people think.

terri cockrell
grand prairie, tx

Dear FRONTLINE,

We learned about the number of animals who have died during this surgery. Only one monkey lived about 30 days. At what point do we learn, recognize failure and move on? For the cameras a surgeon did the same surgery so he could see it firsthand. That isn't arrogance it is medical stupidity!

I empathize with those who need transplants. We need to educate everyone about the need for organs and look for other alternatives. People die everyday, medicine keeps many others alive without regard to quality. We don't publicize the need for organs because there is such an aversion to death. Life at what cost and why? Death is a natural part of the life cycle.

The answer may be just around the corner, but xeno transplantation is a slippery slope to disaster for all species. We are smarter than this!

Joan Joyce
fullerton, ca

Dear FRONTLINE,

In an age when the human population on the planet has surpassed 6,000,000,000 and the population - the very existence - of a whole host of other species declines, one has to wonder about the sanity of killing tigers for their penises or bears for their gall bladders to further heighten human fertility.

In the same way the Frontline "Organ Farm" special forces us to ponder the morality of raising animals for their organs, at the risk of infecting the human population with a transgenic agent or virus. While there is no denying the suffering of the animals used for the medical experiments, each person who vociferously opposes the use of animals for experimentation knows they must address the question "what if it were my son / daughter / brother / sister / wife / parent?" Perhaps you would choose to have a loved one die rather than be associated with suffering animals used for experimentation, but many, perhaps most, would choose to accept the cost. We eat pigs by the millions anyway, right? As long as there are those who will accept transgenic organs the research and experimentation will continue, and there will be a level of acceptance.

So where do we draw the line? Organs that pump or filter or digest are functional - what if one day we can transplant the brain of a dolphin or a bonobo to a human? Given the choice there would certainly be those who would accept the mind of a dolphin in their child over the death of that child. We have essentially decided, as a medical community if not a population, to accept the risk of introducing a transgenic disease to the human population. Does it follow that we would reject a transgenic organ for a dying child if we could instead use their own cells to clone them anew? Many, given the choice, would say yes. Some would say no, it simply isn't worth the risk, the moral debility.

But we will be in the minority, and the race will continue on its trek to a brave new world. Beyond a powerful sense of curiosity, I rather hope I don't live to see it.

Scott Goetz
hyattsville, md

Dear FRONTLINE,

Thank you Frontline for your excellent program, once again going where most media fear to tread. What folly to risk unleashing viruses that could kill far more people than animal organs might save -- and how perfectly obvious that the whole enterprise is grossly unnatural when nature cries out with a massive immunological rejection of foreign organs. Putting human genes in pigs, then putting the pig organs in humans, with no idea whether we will create new viruses or be able to control the consequences ... have we lost our minds?

Even if we haven't lost our minds, we have lost our decency to other creatures on this planet. Without questioning whether researchers, doctors and maybe even the companies who see a way to earn millions of dollars are in good faith seeking knowledge and a way to save some human lives, I fail to see a moral difference between what they are doing and the research the Nazis did on their prisoners, which the Nazis also intended to advance science and knowledge and potentially save the lives of those few the Nazis thought were worthy.

The best the researchers can come up with is that if we can raise animals for food, why not for their organs? But rather than justifying our folly and cruelty, the argument leads to the further question why we should make billions of animals every year suffer gross confinement, filth, pain and terror to raise them cheaply for our overconsumption (particularly with so much evidence that it is neither necessary nor healthy to consume meat and dairy). Thank goodness for those "animal rights extremists" who dare to question all this. One day we will understand the defenders of the status quo in the same light we now understand why so many people -- thought to be decent and moral in the time in which they lived -- thought slavery was OK, too.

david rosskam
washington, dc