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In April, a distinguished group of scientists and legal experts gathered in San Francisco to discuss two of the most exciting and controversial research topics of the century: stem cell research and xenotransplantation.
In April, a distinguished group of scientists and legal experts gathered in San Francisco to discuss two of the most exciting and controversial research topics of the century: stem cell research and xenotransplantation. (See "At the Table,") David Earp, vice-president and intellectual property counsel for Geron, began with a historical perspective on the politics of stem cells.
Roundtable participants, seated at table, left to right: Anne Montgomery, Wayne Koberstein, Liz Howard, Bill Anthony, David Earp, Thomas Sanders, and Margaret McLean.
Earp: Back in 1995, when Geron started to find ways to drive embryonic stem cell research, federal funding for such research was not permitted. Pharma companies were unwilling to invest in such a politically sensitive area, and few biotech companies were interested. But Geron decided to fund research at three universities. In 1998, Dr. James Thomson at the University of Wisconsin was the first person to successfully isolate human embryonic stem cells. Dr. John Gearhart at Johns Hopkins University was the first to isolate the human embryonic germ cell. (Embryonic germ cells have not received as much attention as embryonic stem cells, even though they may have similar potential.) Geron also funded work at the University of California, San Francisco, in the laboratory of Dr. Roger Pederson.
When scientists first began publishing papers about the research, several groups, including patient advocates, recognized stem cells' therapeutic potential and started lobbying for federal funding. Clinton administration attorneys prepared an opinion, interpreting the federal appropriations act that prohibited using federal funds for research on human embryos. Their opinion was that, since an embryonic stem cell was not an embryo, NIH [National Institutes of Health] funding of research on embryonic stem cells was permissible.
At the Table
When it took power, the Bush administration reviewed the Clinton decision and, in August 2001, announced that federal funding would be permitted only for research using already-existing embryonic stem cells. In other words, federal funding could not be used to create new cell lines or to work with cell lines created after 9 August 2001, the date of the announcement.
Researchers can now apply through NIH for federal funds to work with "qualified" human embryonic stem cell lines. We at Geron see that as a very positive step. It allows companies to work with academics and universities on embryonic stem cell projects without jeopardizing their federal funding. Now the discussion has turned to whether the Bush decision will be expanded to include new cell lines.
It's important to point out that the political debate relates only to federal funding of human embryonic stem cell research. It doesn't have much impact on the ability of private companies like Geron to continue pioneering such work. New cell lines are clearly necessary, and many companies are already creating them.
Wayne Koberstein: I'm a little surprised by your evaluation of the Bush decision. Do you mean that any decision was better than no decision at all, so work could proceed? Would you prefer that the decision was more open to stem cell research?
Earp: We welcomed the Bush decision because, for the first time, it permits federally funded researchers to work on embryonic stem cells. It was a big step forward. Do we think it would have been scientifically justifiable and more progressive to allow federal funding for future-created stem cell lines as well? Yes, of course. Nevertheless, it's beneficial to the research community and to medicine in general that the research is expanding. This step will help the public become aware of the benefits of the science as progress is demonstrated. We believe that, eventually, federal government funding will be expanded.
The discussion then turned to the practical implication of federal versus privately funded projects.
Earp: The divide is simply on the issue of whether federal funds will also be allowed for working with newly created embryonic stem cell lines.
Thomas Sanders: We went through this process more than 25 years ago when we established recombinant DNA guidelines that apply to federally funded work only. Yet, most of the industry agreed to abide by them because they were scientifically and technically based and therefore workable. There's a subtle difference here. Will this ruling remain workable? With newly created cell lines banned outright from use, it may not. The cells we have now will not meet the need for all the projected uses. We'll have to create new ones that are better adapted to particular applications.
Liz Howard: What about the bills now being considered in Congress: the Specter bill, the Brownback bill, the Feinstein bill? Will they restrict stem cell research more than the present guidelines? Will they affect the full scope of research by private companies?
Earp: The bills mentioned relate to cloning and seek to outlaw various activities by both private and public entities. There is almost universal agreement in the industry and among the public in general that reproductive cloning-the use of nuclear transfer to produce live-born human beings-should be prohibited. More controversial is the use of somatic cell nuclear transfer to create the human blastocysts from which embryonic stem cells could be derived. That is, nuclear transfer not for the purpose of reproductive cloning, but to produce embryonic stem cells.
Some people believe that somatic cell nuclear transfer could ultimately produce embryonic stem cells with a patient's perfect genotypic match. You could then differentiate the stem cells to neurons to produce a patient-specific therapy. However, we don't believe patient-specific treatment is a widely adoptable therapeutic modality. It would be very expensive, difficult to implement for large numbers of patients, and a model that the pharmaceutical industry has never embraced.
Geron's model for producing therapeutics from embryonic stem cells is to create something that can be of benefit to a large number of patients. For instance, we're talking about creating a universal donor cell similar to type O blood, which most people can tolerate. Such cells could be the next generation of pharmaceuticals: instead of pills in a bottle, we'd have cells in a bottle.
Even though we don't believe patient-specific therapeutics are the best use of somatic cell nuclear transfer, we do believe they should be permissible for the sake of science. Nuclear transfers put a somatic cell into an oocyte, which reprograms the somatic cell. It's dedifferentiated, taken back to something capable of giving rise to any of the cells in the body.
Standoff on Capitol Hill
We believe that somatic cell nuclear transfer should be allowed so the factors responsible for that can be elucidated. If we could isolate and characterize those factors, eventually they might be used more facilely than nuclear transfer to reprogram somatic cells.
Is somatic cell nuclear transfer necessary for the future of embryonic stem cell research? Absolutely not. The cells that exist today were not created through nuclear transfer; they were isolated from in vitro fertilized (IVF) embryos that were scheduled for destruction.
What is generating the greatest public enthusiasm is the potential to make patient-specific tissues. There's a rhetoric of persuasion that doesn't reflect the science. What's going on in biotech companies is very different from the conversation you hear in the public square. People like the idea of creating tissues for this particular diabetic or that particular Alzheimer's sufferer. Part of that is our penchant for saving one person, even at the expense of many. We see a large disaster as merely a large disaster, but one hurt person really tugs on heartstrings. There are ethical dimensions to our public conversations about patient-specific therapies.
Bill Anthony: We seem to have a unanimous view against reproductive cloning. But isn't making cultures of stem cells getting pretty close to cloning an organ?
McLean: The fundamental thing that troubles people about stem cells is what Art Kaplan and Glenn McGee have called the "What's in the dish?" question. When you look at those cells in the dish, what do you see: a "protectable human person" or a culture of human cells much like any other? That has been the most polarizing debate, and it has derailed other important concerns. We're still stuck there.
A further ethical consideration that has been waylaid by the "What's in the dish?" question has to do with safety. There's a deep reason to be concerned about safety if, indeed, the research is restricted to existing stem cell lines. As cells age, they are more likely to mutate and, therefore, be more problematic when transplanted back into humans. Safety is the stopper for human reproductive cloning, but we don't talk about it enough in terms of stem cells and nuclear transplantation.
Another concern is the treatment of egg donors. Look at the numbers for some of the animal studies: You have a success rate of one in 300–500. If you think about using 500 human eggs for every cell line you establish through nuclear transfer, that generates questions about exploitation of women, payment, commodification, and other issues.
Earp: Although it's clear that new lines will be beneficial-and some have already been produced-the existing lines may be useful for certain product applications. Aging of the embryonic cell lines isn't likely to be a significant problem. First, we know that the cells maintain a normal karyotype after many hundreds of population doublings but second, and most important, it's standard practice to establish cell banks. So, you simply go back to the banks of "young" cells to start production runs. In other words, you don't have to rely on the fidelity of older cells.
In terms of the efficiency of animal cloning, the 300–500 eggs used for each successful cloning would apply to producing live offspring, and those numbers are improving all the time. For instance, the efficiencies are much higher now in cattle cloning. But it's also important that those numbers apply to reproductive cloning-getting all the way to a live-birthed animal.
The success frequency for producing blastocysts from which embryonic stem cells could be isolated is much higher. It's important to remember that most of the failures in nuclear transfer occur after the creation of the blastocyst. So, at least, based on the data available from cattle cloning experiments, the ratio of eggs used per blastocyst produced would be significantly lower. Of course, we don't know what the efficiency of somatic cell nuclear transfer would be, using human cells.
The discussion now turned to the question of whether patents should be allowed for biological materials.
Sanders: If humans have manipulated what's in the dish or isolated it from a mix in which it could not be approached before, it is, in principle, patentable. I think the people who invest huge amounts of money in creating healthcare products should benefit from their investments. Those who carry out research that eventually produces a product should be able to sell that product under a patent. There's nothing wrong with that.
Anthony: Doesn't that affect ethical concerns?
McLean: Right or wrong, in the public mind patents are equated with secrecy and ownership. When you start talking about owning the byproducts of human reproduction, such as pre-embryos and blastocysts, the desire to "stiff-arm" becomes very, very strong. People raise ethical concerns about patenting-particularly about patenting genes, pre-embryos, stem cells-things that people identify with "what makes me me."
Sanders: For 30 years, we've discussed genes, proteins, isolating cells, materials isolated from animal cultures, and so on. We generally conclude that, if there's significant human involvement, a product is patentable. Patent laws create a relationship between society and inventors. The laws say to inventors: "Share your science publicly with us, and we will protect it so nobody else can use it for a limited time." The alternative is a trade secret arrangement in which companies work behind closed doors. I believe it's better to have information out there and to protect it under a patent than to force people into secrecy.
Howard: There is a corollary with regard to the public. Patent law is misunderstood. In fact, it's the epitome of the public process. There is a misconception that ownership is attached to a patent. Instead, it merely confers the right to exclude others. There's a real need for education, heightened by the public perception that these are patents on human life forms.
Anthony: Geron patents the products of stem cell research. Have you seen any resistance, based on ethical concerns, to protecting your company's products with patents?
Earp: I think everyone at this table agrees that there is a huge therapeutic potential for human embryonic stem cells. If such cells were not patentable, we wouldn't be here discussing potential uses of the cells. Without intellectual property protection, companies would have no incentive to make such investments. Geron never would have funded the work in the first place, and the cells might never have been isolated. The patent system enables the whole discussion.
Are ethical issues considered in the patent system itself? Not in the United States. Some 1920s cases invalidated gambling machines' patents on the basis that they served immoral purposes, but that law is no longer followed. But no statutory construction in US patent law addresses ethics or morality.
Europe has a morality clause. Once the European patent office decides to grant a patent, it publishes a notice and invites people who believe the patent should not be granted to oppose it. The contrary-to-public-morality provision is frequently invoked in those opposing statements. Several such oppositions have been filed during the past few years, mostly by the European Green Party.
A classic example is the Harvard oncomouse patent, which went through a protracted opposition proceeding. People objecting to the patent argued that the suffering of the mice, which were genetically engineered to develop tumors, outweighed the potential benefit of the cancer therapeutics that might be developed. Nevertheless, the patent is likely to stand.
Koberstein: Is the Bush administration trying to introduce a morality clause in establishing its bioethics committee?
Earp: I haven't heard that. Patent law is the wrong place to introduce such considerations. We have ample regulatory review of products and research. For example, all experiments involving humans or animals, whether done in universities or by companies, are methodically reviewed and must be approved by institutional review boards. Some companies, including Geron, have independent ethical advisory boards. Our editorial advisory board reviews all planned human embryonic stem cell experiments.
The United Kingdom, Canada, and Australia all have less restrictive policies than the United States. Australia recently passed legislation that allows the creation of stem cells from any available IVF embryos created before April 5, in addition to existing stem cell lines.
Sanders: Ultimately, if the United States provides too many barriers to the research, it will simply move offshore, as did recombinant DNA. Other nations will welcome it. The quest for scientific peer recognition, or perhaps commercial exploitation of technology, will make it happen. Then the United States will be behind, and we'll have less control than if we had adopted some sort of process to make it happen here.
Anthony: Are we seeing movement to go offshore with stem cell research?
Earp: To some extent. Geron has an operation in Edinburgh. When we acquired the Dolly cloning technology, we committed to funding work at Roslin Institute. Because we have skilled researchers, we fund work in human embryonic stem cells there as well. Is that an operations base we could use, despite the US political climate? Yes, absolutely. The British government's endorsement of human embryonic stem cell work is very progressive, and it is making government funds available.
Anthony: Are the various restrictive legislations pending today in the United States creating a distaste for investment in stem cell research here? And are investors moving to Europe-not just Geron but Geron's competitors?
Earp: I don't know that the pending legislation has induced that yet. Human embryonic stem cell research will continue regardless of which, if any, of those bills is enacted into law. I think everyone is hopeful that the voice of reason will prevail in the legislature.
Asilomar happened 27 years ago. (See "Where It All Began,") It was a first, little step. Gradually, what went on there became assimilated in society. Rules evolved over time. We're likely to see a similar progression here. You take baby steps; they're accepted and maybe even embraced. It's good to have a forum talking about this before the public. We haven't done that before.
In 1978 or so, I taught a course called "Man, Molecules, and Morality" and another one a couple of years later called "Biology for Poets." The purpose was to introduce my students to concepts such as gene manipulation and test tube babies. The point was that they were going to have to cope with those concepts.
Where It All Began
However, such discussions went on largely between scientists in university enclaves; there wasn't much of a public dialogue. Getting it out there in a way that brings the public, politicians, lawmakers, and policy makers up to speed is important. Maybe this is the beginning of that. We don't want legislation spurred by hasty reactions such as: "Oh, my God, look what they've done now. Let's regulate, fix, repair, understand, or study that in the next 30 days and come up with an intelligent law."
McLean: One big benefit of federal funding, and of the patent process, for this type of research is that it brings the science to the public's attention. Part of what's behind the "unethical scientist" motif is the attitude that says, "We don't know what you're doing, and we don't trust you because of that." So, the National Bioethics Advisory Commission (NBAC), the current president's ethics advisory committee, federal funding, the patent process-all of that bodes well for public understanding and conversation about biotech in general, a subject that frightens a lot of people.
Anthony: So, are we in a transitional stage? What we started with is the public's knee-jerk reaction to what seemed like a black and white issue. But as soon as someone like Michael J. Fox is cured-one person saved-will that change public opinion? And once it changes, will an unlimited number of cell lines be opened up to federal funding?
I discussed that subject last year with Christopher Reeve. Many people say that stem cell research has been overpromised. Is that a factor?
Sanders: Every biological breakthrough-genetic engineering, organ transplantation, gene therapy, cell therapy-has been overhyped. They are greeted with enthusiasm and then, because things are never as easy as they seem, they sink into a nadir more pessimistic than is warranted. Gradually the breakthrough reemerges as a solid, scientifically based project and product area. Monoclonal antibodies [MAbs] were touted as "magic bullets," then virtually forgotten by the public and most of the industry. The first MAb-based products just emerged in the past few years. It took 15–20 years for that initial promise to be delivered. We're likely to go through that sort of boom–bust reality cycle with stem cells.
McLean: Two things are different in this context. One is the large amount of investor money going into the research at biotech companies because of the lack of federal funding. We started that in the Reagan years, with federal money being squeezed out of the scientific research arena. Things have shifted from the NASA model of huge, publicly funded, publicly debated big science to a more fragmented science base. We now have some science funded in the federal sphere, some in the private sphere, and some from both, but we don't have that overarching "big science" cooperative effort.
The second thing is media coverage. Until September 11, stem cells were front-page news in the United States. But it's very difficult science. The subtleties between cloning, nuclear transplantation, and stem cells are lost on almost everyone, but they are politically, ethically, and scientifically important. And the context in which this subject is playing itself out is different in important ways from that of MAbs or recombinant DNA.
Sanders: I'm not sure I agree with that. When the public first started hearing about recombinant DNA, it was every bit as arcane and misunderstood as the topics we're discussing here today. But after hundreds of pictorial diagrams in national magazines, recombinant science taught at the fifth-grade level has become relatively commonplace. So part of the issue, as it always has been, is communication.
The biggest fear is the fear of the unknown. Once the public begins to understand the science and its controls, it becomes less frightening. In the '80s, I was involved with a committee reviewing recombinant DNA activities in a town that considered banning them. The committee consisted of a group from the community: a housewife, a reverend, a merchant, and so on. When they walked in, they knew nothing. Once they understood what was really going on, they said, "What's the issue? That's not so bad." It's just a matter of informing people. Right now, the public knows very little. We have a couple of years of profound educational efforts ahead of us.
Glossary of Terms
Anthony: What surveys have been done to determine the public perception of stem cells? Do we know what the public knows?
Earp: I'm not aware of any surveys, but there certainly is a lack of knowledge. And I believe everyone in the industry has a role to play in trying to elevate the level of public discussion. One thing we've seen recently in the debate about stem cells and nuclear transfer and cloning is some sensationalized science and headline grabbing. There are people who love the limelight and companies that, whether they have rights to the technology or not, say they're going to move into this area. We've seen reports of experiments that are probably not real. They have led to controversies, even within the editorial boards of the journals publishing the reports.
So, the confusion is not just among the general public. There is confusion within the industry about who owns the rights, who's doing the work, and which companies will advance the science in responsible ways. We'll be best served by doing real science and publishing it in peer-reviewed journals. The industry needs some self-regulation, and I hope the leading companies will help by setting an example.
Glossary of Terms Continued
Following a discussion of the scientific, ethical, and political issues surrounding xenotransplantation, the discussion turned toward the future of stem cell research.
Anthony: Could stem cell research make xenotransplantation obsolete?
Earp: It's possible. What we're talking about now is the first generation, maybe two generations, of stem cell research. In the first generation, we're talking about produced cells that can be implanted into the appropriate site in the body. They will be single-cell categories, perhaps dopa-minergic neurons to treat Parkinson's disease or myelinating oligodendrocytes to treat spinal cord injury. Those products are not likely to be genetically engineered for immunocompatibility. They will be administered with modern immunosuppressive therapies, which patients tolerate quite well.
The second generation may not be whole organs but structures-unique cells placed in the right type of cellular environment to encourage optimum function.
A third generation might be those same cells engineered to remove the rejection problems, to eliminate the need for immunosuppression. Down the road, we might be able to generate structural organs rather than simply cellular structures, but we're a long way from that.
Anthony: What's the better approach from an ethical standpoint?
McLean: It depends on your perspective. If you believe that what is in the dish is protectable human life, then xenotransplantation will look attractive to you. If you believe that the cells in the dish have weak or no moral status and can make no claim on us for protection, then you might conclude that the scientific obstacles to xenotransplantation are too great. It really depends, as so often it does, on your ethical starting point.
Sanders: If you're a member of PETA [People for the Ethical Treatment of Animals], and you believe that using animals for the benefit of mankind is a bad thing, then you would want xenotransplantation to be banned. There are those whose views seem to place animals above humans.
Howard: We encounter that all the time. How do we develop medical procedures for the heart? We work on dog hearts, isn't that right?
McLean: But that's not ethically acceptable to everyone. There are people who argue that we should not use dogs in that way. In fact, in Berkeley, dogs are no longer called "pets," they're called "companion animals." Such ethics about the treatment of animals come into play when you consider xenotransplantation, even though much of medical research still involves using animals in some way.
Koberstein: There's a big difference between the political clout, at least in the United States, of animal rights activists and reproductive rights groups. The right-wing threat to stem cell research seems more serious than the threat on the left to animal testing. How scientists react to that will affect the public attitude. The public is waiting to hear the other side. Although there is a difference in both science and legislation, between cloning and stem cell research. In people's minds, the word "cloning" has almost taken over stem cell research and everything related to it. Such an emotionally powerful word can color everything. You have to control some of the terms or lose the debate.
Howard: And there are differences, aren't there, in how the proposed legislations deal with somatic cell nuclear transfer and with cloning?
Earp: Yes. Brownback would outlaw somatic cell nuclear transfer, whereas the Feinstein bill would outlaw reproductive cloning and allow somatic cell nuclear transfer to create stem cells for therapeutic research.
Koberstein: That is a significant difference. How do you rationalize the outlawing of somatic cell nuclear transfer when you're not cloning anything?
McLean: One reason is the "What's in the dish?" question. The other-and it's made for strange moral bedfellows-is the "slippery slope" concern. The rationale says, "We could allow you to use somatic cell nuclear transfer to create stem cells for research. But someone might take one of those embryos and implant it into a woman and we'll have a cloned baby." Or it says, "The very existence of those stem cells and pre-embryos, those blastocysts from which you harvest stem cells, makes you complacent."
The third argument is the concern for egg donors. If technology creates a need for a large number of human eggs, that creates a potential for exploiting women. Those were among the issues that we considered on the California State Advisory Committee on Human Cloning.
Sanders: I don't believe in the slippery slope theory. All things have potential for good and evil. One man or one nation might decide to build a biological warfare device. But we've decided as a society that the benefits of healthcare outweigh such possibilities. The same is true here.
Howard: Isn't that better addressed with regulation as the dangers come up? It emphasizes the need for better educating the population, starting in grade school.
Anthony: If we have a somatic cell nuclear transfer, can scientists make a baby from that?
Earp: The processes for somatic cell nuclear transfer and reproductive cloning are indeed similar, particularly in the early stage. But those processes would differ dramatically after the blastocyst stage.
I'd like to return to the morality issue for a moment. Most people justify their opposition to reproductive cloning based first on safety issues. Today the success rate of animal cloning is low. Cloning a human being right now would require vast resources and be impractical, inefficient, and dangerous. There are clear safety reasons to say we absolutely shouldn't permit it today. But one day it might be more efficient. Therefore, I'm not comfortable that we're answering the real question if we base moral opposition to reproductive cloning on safety. It would be interesting to push through and say, "Once the process is 100 percent safe and efficient, how do you feel about it then?"
McLean: The California State Advisory Committee on Human Cloning believed that the National Bioethics Advisory Commission did a great job in addressing human cloning, but that it didn't get where it needed to go. They did consider the safety issue and decided we should not use this technology to produce a child because it is not safe and efficient. We in California agreed, then tried to push further. All 12 committee members agreed that human reproductive cloning ought to be banned for safety and each cited additional reasons as well. Some were concerned about societal harms; others were concerned with the regulatory nightmare. There could be good reasons and bad reasons to clone a child. But all of us agreed that, safety aside, we still would not recommend permitting human reproductive cloning.
Another issue that overarches all of this is the question of distributive justice. Once there are cells in the bottle or organs in the lab, how do we distribute those resources?
An increasing number of people have lost health coverage. There are close to 43 million uninsured Americans. When the new technologies become available, how will we get them into the healthcare system? What will the market allow and not allow, and how should we think about distributive justice and access? Now is the time to think about that.
Sanders: We've confronted this issue with every new development and we do go forward, though not perfectly. There are already $100,000 procedures being performed; bone marrow transplantation is one example. It's horrendously expensive, but it is now a treatment of choice. I don't think distributive justice-or lack of it-is a reason not to do something. Expense may be one reason we can't apply a therapy or technology at the level we would like to, once it's available, but I don't think it's a reason to stop.
The California State Advisory Committe on Human Cloning suggested creating some kind of public body to review and disseminate information about biotech developments to the public. Many of the new technologies frighten people, and perhaps a source of reliable, understandable information would ease some of their fears.
One issue that should be addressed is embryo splitting, which is another way to "clone" a human being. That procedure is neither addressed nor prohibited by the proposed legislation, and it raises ethical questions that are different from those concerning somatic cell nuclear transfer. There are many new developments on the horizon. If we can bring the public into the conversation and assure them there will be regulatory enforcement, it will allow the good stuff to go forward and keep us off the slope into Dante's Hell.
Sanders: One reason these things may be better addressed offshore is that most Europeans have a better science education than we do. How many US high school kids take physics? Just 28 percent. How many know any biology or chemistry? We have eviscerated science education in this country, yet we expect our citizens to be able to make judgments and political decisions about things like stem cell research.
We must try harder to produce technically educated people who know what a clone is. Then much of this will no longer be a feared unknown. As we have become a technocracy, we have become less educated. How many members of Congress have an undergraduate degree in the sciences or a graduate degree in technology? Probably a handful. Yet, we expect them to make responsible decisions about issues like stem cell research.
Cloning is one example of a concept about which there is an almost universal lack of understanding. Everyone has heard of Dolly, the "cloned" sheep. But a clone is a population of cells with the same genetic makeup, typically derived from a single cell. Dolly is not a clone, nor are most of the other clonal organisms, because part of their genetic makeup lies outside the nucleus.
I work for MitoKor, a company that studies mitochondria. That portion of the genome that's not in the nucleus sits within the cytoplasm, in the mitochondria. Every type of nuclear transfer experiment involves removing a nucleus from a donor cell and putting it into a recipient cell with a different mitochondrial makeup. Thus, the result is not a true clone. That fact may well have an impact on the resulting cells or on the animal produced.
We know that mitochondria have proteins that are derived or encoded in the nucleus and others that come from or are encoded in the mitochondrial genome. There is reason to believe that an appropriate balance, matching, or genetic harmony between the two is necessary for proper mitochondrial function. Also, mitochondrial genes can mutate. Mitochondrial problems can cause devastating illnesses.
That's more than the public wants to know, but it is an example of how misinformed the public is and how much we need a more thorough education.