Stored tissue samples: Gold mine or land mine?

Bioethics policies not keeping pace with technology

Hospitals across the country may be sitting on a research gold mine and not even know it. Thanks to the "mapping" of the human genome, stored blood and tissue samples from patient screening and research projects could provide a wealth of information to researchers studying the links between genetic mutations and disease. "An interesting area that may be of particular importance is the issue of residual newborn screening samples," explains Jeffrey Botkin, MD, professor of pediatrics and medical ethics at the University of Utah in Salt Lake City.

Every baby born in the United States has a blood sample taken so that the baby can be screened for a number of diseases. Although the particular tests vary from state to state, most include a screening for hyperthyroidism, phenylketonuria, and sickle cell disease, among other things.

"You virtually never use up all of the sample in conducting the tests," Botkin continues. "So, they may sit around. Laboratories may use them to recheck their instruments for quality control. But, they are also sitting there and available for testing a wide variety of things. Some states in the past have used them to anonymously screen for HIV prevalence in the population. They could potentially be an extremely valuable resource to look for prevalence of genes or infections or environmental exposures."

Is consent even necessary?

Although most hospitals currently are not set up to allow researchers access to the tissue samples, the fact that they exist raises questions about whether these samples could be used in genetic research. Should hospitals go back to individual parents, or the now-adult donors themselves, for consent to use these samples in research? Or, since the samples are considered the property of the institution maintaining them, is consent even necessary?

These screening samples represent just a fraction of the massive amount of stored tissue samples that could potentially be available to outside researchers, say Botkin and others.

"We have the gathering of information for forensic purposes, storing blood and tissue samples of convicted sex offenders, for example," adds C. Ben Mitchell, PhD, senior fellow with the Center for Bioethics and Human Dignity in Bannockburn, IL. Mitchell also is an assistant professor of bioethics and contemporary culture at Trinity Evangelical Divinity School and Trinity International University in Deerfield, IL.

"Also, information from federal employees and military personnel. All of that information is either available or might be available out there. I don’t want to sensationalize the issue. But, all of those samples from military personnel and federal employees are stored somewhere inside the Beltway."

Large databases of genetic information are valuable to researchers because they would allow them to study a certain prevalence or occurrence of a genetic trait across a large population, often a population about which significant demographic data already were collected. At the same time, this also means that very specific information about large numbers of individuals has the potential to become public, points out Mitchell.

"The specificity of our genetic information, the fact that it can be used to identify an individual, kind of raises the stakes," he explains. "It is not just that we are tracing the incidence of breast cancer now. It is that, at some point, we might be able to go down the line and see exactly who that was who had the breast cancer. That would be a potential violation of privacy."

There already have been instances of what many ethicists would consider to be wrongful use of information gained through genetic testing, says Mitchell. Which means that as the amount of stored genetic information becomes more easily available, the potential for abuse increases exponentially. "That fact demands that we begin to think about how we will use that information, and how we will protect patients’ rights with respect to that information," he says. I think it would be naïve to assume there won’t be a lot of people who want access to the information."

A precedent-setting lawsuit in California, Moore v. Regents of University of California, set a benchmark in determining what rights individuals have with respect to blood and tissue samples after they’ve been collected. The ruling had an enormous impact on research and development of genetic therapies and diagnostic tests.

A California man, John Moore, was being treated by his physician for hairy-cell leukemia, explains Botkin. His physician, however, also was an investigator. The physician developed and patented a cell line from Moore’s blood and tissue samples.

"There were some questions raised about whether additional blood samples were taken that were not necessary for medical care," Botkin continues. "At any rate, the investigator ended up getting a patent for a cell line and a relatively lucrative commercial product. Moore found out about it and sued for a share of the profits."

In 1990, the California Supreme Court ruled that Moore no longer had property rights to his genetic information. However, it also ruled the physician should have gotten his informed consent before collecting information for research purposes. "Investigators had an obligation to inform research subjects that their materials might be used in the development of a commercial product," Botkin explains. "If they wanted to opt out, then they could. It came down to more of a consent issue rather than an ownership issue."

Since that time, a number of research projects started including standard language in their informed consent documents stating that information obtained from tissue samples may be used in the development of a commercial product, but that the donor won’t have a share in the profits of that development. "It seems clear, at this point, that samples that enter a laboratory are no longer owned by their source," he says. "But, people should still have the option of opting in or out of the research."

Allowing research using anonymous samples

But what about tissue samples already collected and stored? The National Bioethics Advisory Commission (NBAC) examined the issue in depth, says Botkin.1 And its conclusion, and the way that most institutions have decided to handle that issue is by unlinking the tissue samples from identifying information about the donors or tissue source, which eliminates the privacy risk to the individual, he says.

"Thus, the donor no longer becomes a human subject as far as institutional review boards [IRBs] are concerned," he explains. "Now, the IRB may be interested in reviewing your protocol for unlinking the information. But I think that has been a good route to reduce concern."

The potential for unlinked information to still stigmatize large populations however remains and has yet to be dealt with, Botkin adds. "For example, you know your samples are from an African-American or Native American population. You may find certain traits that are more prevalent in that population than others. You can potentially stigmatize the whole population even though individuals have been protected."

Use of linked or coded samples — samples maintained with the identifying information from the source — for new research projects that the donors did not consent for is now very much "frowned upon" by the research community, Botkin says. "If you want to use linked samples, re-consenting seems to be the appropriate way to go."

Some researchers attempt to address the issue of future uses of genetic information by including statements in the informed consent process for one study, which asks the participant to consent to use of the samples and information in future studies. "That’s the remaining area with the most controversy right now," Botkin says. "Basically, the question is whether people can sign away their consent to future research on identifiable samples." Can, for example, a researcher reasonably ask a person to allow his or her identifiable sample to be used for whatever purpose it could possibly be used for?

"NBAC split on that," he says. "Some people said that if people are informed and can make the choice to allow their sample to be used for anything that is their prerogative. But, others felt that you really cannot give informed consent for research unless someone tells you exactly what the research is that the tissues are going to be used in."

Botkin agrees informed consent requires a participant to know and understand the information and effects of a particular study. "I think it is reasonable to ask folks, for example, Can we use your sample for this study involving cancer research and other cancer research studies?’" he says. "But, to turn that around and use it for Alzheimer’s research without going back for additional consent, I don’t think is reasonable."

It is also impossible to know, given the current pace of genetic research discoveries, exactly what kinds of information we may be able to extract from tissue samples in the future, adds Mitchell. Therefore, any sort of "blanket" consent is invalid. "There is a time span problem in that in 2001 we are not able to determine or predict what we might be able to test for in 2050," he says. "We need to be as scrupulous as possible in protecting that information because we do not know what information might be able to be gathered in the future."

Some ethicists have gone even further, arguing that study participants — and even patients submitting to medical testing — should be able to mandate that their biological samples and information be destroyed, Mitchell adds. "Not only must I be able to give consent for a particular test that might include a genetic screening or gathering of genetic information, and consent specifically to that particular use and to no other, it may also be possible for me to say that I want my sample destroyed after that information is gathered so that it is not stored somewhere."

That raises more questions about the rights patients have to their genetic information, and about how much information can be obtained even after the tissue sample is destroyed, he continues. "We need biologists to tell us the answer to that. How much information are we able to gather right now that is above and beyond what is needed for a particular test and what is the best way for that information to be protected."

Unfortunately, say both Botkin and Mitchell, bioethics policy is falling behind the pace of scientific advancement, creating the potential for abuses of genetic information on a large scale. The NBAC has done a lot of work in this area and written position papers and recommendations, says Botkin. But, the Department of Health and Human Services’ Office for Human Research Protections has not released any formal policies or standards to govern hospital ethics committees or IRBs.

"We are stretching our existing structures almost to the breaking point," says Mitchell. "These new technologies are going to demand our rethinking [of] our regulation and policy because the potential power of these technologies for gathering information is of a magnitude greater than we have possessed in the past."

(Editor’s note: The National Bioethics Advisory Commission’s report, Research Involving Human Biological Materials: Ethical Issues and Policy Guidance, is available on the commission’s web site: www.bioethics.gov.)

Reference

1. National Bioethics Advisory Commission. Research involving Human Biological Materials: Ethical Issues and Policy Guidance. Vol I. Rockville, MD; 1999. 

Sources

Jeffrey Botkin, MD, University of Utah, Pediatric Administration, School of Medicine, 50 N. Medical Drive, Room 2A152, Salt Lake City, UT 84112.

C. Ben Mitchell, The Center for Bioethics and Human Dignity, 2065 Half Day Rd., Bannockburn, IL 60015. Web: cbhd.org.