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A History of Bias: The Tuskegee Syphilis Experiment

January 19, 2020

We’ve come a very long way in the way we perceive medicine and how we use it. We’ve grown from studying the humors of medieval times and performing brain lobotomies in the 1900s to the most complex surgeries and medicines that can save millions of lives. But sometimes the question that isn’t asked is, what was the cost of this new knowledge? Were the decades of long, painstaking research and repeated experiments worth it when some subjects were put through experiments that ended in permanent injury or their death? There has always been a long and dark history to the cases of medical bases, especially in the case of race, sex, and gender. In this article, I want to focus on racial bias, discussing the story of the Tuskegee Syphilis Experiment, why it is an example of medical bias and the impact that this bias made on history and future research.

What Started This?

In 1932, a study was started by the Public Health Service to study the natural history of syphilis to justify treatment programs for black males. The experiment was meant to build upon a similar study on untreated syphilis in Norway in 1928. The initial goal of the study was to follow the disease in black men for six to nine months, and have a treatment phase for the subjects after. The study took place at the Tuskegee Institute in Alabama and the subjects were recruited from Macon County, which is part of the Black Belt, a region with rich soil and black sharecroppers. The participants were mostly poor and illiterate, signing up mainly for the benefits described to them. About 600 participants were recruited, 399 who had untreated syphilis and 201 who acted as control subjects.

What Went Wrong?

The problem with this study that caused so much controversy was what the research participants were told about the study and what would happen to them. The participants were told that they were being treated for bad blood, which was used to describe issues like fatigue, anemia, and syphilis. They were told that they would receive medical exams, rides to and from the clinics, meals on examination days, free treatment for minor ailments and guarantees that provisions would be made after their deaths in terms of burial stipends paid to their survivors. The participants were told that the study would last for six months in 1932, but it went on until 1972. Another problem with the ethics of the study was the fact that the participants gave no written or informed consent to be experimented on. There was no evidence to show they had an option to leave the study, and the treatment they were given was slightly effective and highly toxic. After years of research and generations of unknown diseases transferred to spouses, children, and many affected, a report by the Associated Press was released in 1972 about the experiment, which was then forced to shut down a month after. Even though a class-action lawsuit led to nine million dollars given to the participants and an apology was given by President Clinton, the consequences brought to the participants and their families couldn’t be undone. The last survivor of the experiment passed away in 2004, and the last widow receiving benefits from the Tuskegee Health Benefit Program passed away in 2009.

A memorandum from the Department of Health, Education and Welfare in November 1972 requiring the Tuskeegee Syphillis Study to be terminated, and for all remaining “participants” to be given the cure.

How Has It Affected Research & Medicine Today?

Despite the heartbreaking story of the Tuskegee Syphilis Study, it has helped to change how researchers approach studies similar to it. The study led to the creation of the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research and the National Research Act, as well as the establishment of institutional review boards, or IRBs for institutions receiving federal support. Since the end of the study, IRBs require that all participants in a study are willing and voluntary patients. In the end, because of the syphilis study, the U.S. was able to become a more ethical place for research, even creating the Tuskegee Bioethics Center, a national center for research and health care.

Sources:

About the USPHS Syphilis Study. (n.d.). Retrieved October 25, 2019, from https://www.tuskegee.edu/about-us/centers-of-excellence/bioethics-center/about-the-usphs-syphilis-study.

Brown, D. N. L. (2019, August 26). ‘You’ve got bad blood’: The horror of the Tuskegee syphilis experiment. Retrieved October 25, 2019, from https://www.washingtonpost.com/news/retropolis/wp/2017/05/16/youve-got-bad-blood-the-horror-of-the-tuskegee-syphilis-experiment/.

CDC. (2015, December 22). Tuskegee Study – Timeline – CDC – NCHHSTP. Retrieved October 25, 2019, from https://www.cdc.gov/tuskegee/timeline.htm.

Heller, J., Burns, L., Merritt, C., Corine, Thompson, M., Sam, … Bryant, D. (2018, April 13). Generations later, the effects of the Tuskegee syphilis study linger. Retrieved October 25, 2019, from https://www.statnews.com/2017/05/10/tuskegee-syphilis-study/.

Jones, J. H. (1993). Bad blood: The Tuskegee Syphilis Experiment. New York: Free Press.

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About Author

Hi, y'all!

I'm Jalen, a Master's student studying Materials Science and Engineering at Georgia Tech! As part of my thesis, I'm researching different ways to build organic cells. I'm a part of Charged Magazine because I want to show my love of science through articles, videos, and interviews. I also hope to educate people about multiple facets of diversity in STEM.

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  Timothy Durham was convicted of rape when a test showed his DNA genotype matched the DNA recovered from the crime scene. Eye witnesses testified that Durham was in a different state at the time of the incident, but he wasn’t exonerated from his 3000 year sentence until follow up DNA analysis showed that the preliminary forensic analysis used in the trial was misinterpreted (Thomas et al.). DNA testing serves an invaluable part in our criminal justice system, but it comes with complications and bias that can lead to wrongful convictions and misinformed juries.  

Background:

Forensic genetics aims to identify the origin of a biological sample. It can be traced back to Karl Landsteiner who discovered human ABO blood groups. With blood groups, suspects could be eliminated based on their blood type. For example, if a suspect had type A blood and there was type B blood left at the scene by the perpetrator, the investigators could rule out the suspect. Unfortunately, the reverse didn’t work. If the suspect and perpetrator both had the same blood type, it can’t be concluded that the suspect was guilty. Blood identifiers evolved into 8 distinct categories which improved the ability to eliminate suspects, but could only conclude that (if the system matched) it might be the perpetrator or this person might be related to the perpetrator (Jobling and Gill). The field evolved in the 1980s with the discovery of Minisatellites, lines of repetitive DNA that don’t encode proteins. Minisatellite patterns in DNA create what we know today as the DNA fingerprint, and it has a much higher accuracy rate than previous methods (Augustyn et al.). Around the same time, a breakthrough for victims of sexual assault was discovered. In the case of assault, bodily fluids of both the victim and the assaulter can get mixed. A process called differential lysis was created which could selectively increase the concentration of sperm in a fluid sample thereby allowing for accurate DNA testing (Jobling and Gill). Forensics evolved to use single-locus probe testing after several years because of its ease of interpretation. It looked at specific minisatellites that had high variability between subjects. This was the first DNA-based method to be used in a criminal investigation. Two murder homicides from several years apart were connected using DNA evidence. The evidence was then used to exonerate an innocent man, and the guilty party was found when he tried to evade mandatory DNA testing for all men in the small town. His guilt was then reinforced when the DNA profiles matched, and he gave a confession (Jobling and Gill). Finding DNA at a crime scene doesn’t guarantee that you’ll find a murderer. There are issues with non-pure samples and limited samples that make DNA work difficult, and accreditation of facilities and new techniques and take time (Jobling and Gill).  

Subjectivity of DNA Interpretation:

In a 2009 publication, the National Academy of Science discusses the possibility for subjective influence in lab based forensics. The interpretation bias happens in complex cases where, for example, there could be a mixture of DNA. A study published in 2011 looked specifically at this issue. A gang rape happened in Georgia, and the mixture in DNA from the case was used to prosecute one suspect after another suspect took a plea bargain to testify against him. With DNA mixtures, there are three possible conclusions: suspect excluded, suspect cannot be excluded, and inconclusive. If the suspect is excluded, it means that there’s little to no possibility that his DNA is part of the sample. If the suspect cannot be excluded, it means that there’s a possibility that his DNA is part of the sample. In the trial, the DNA examiners who knew the context of the case concluded that the suspect being prosecuted could not be excluded. The 2011 study gave the DNA evidence from this case and the DNA profiles of the suspects to 17 forensic examiners. These examiners had no context of the case, and they all worked independently. Of the 17, only 1 came to the same conclusion (suspect cannot be excluded) as the examiners who knew the context of the case. Twelve of the 17 concluded that the suspect who was prosecuted and convicted had no relation to the DNA found in the sample. Not only does this show that subjectivity occurs due to the context of the case, but the 17 examiners came up with different findings based on their past experiences meaning that not all DNA analysis is objective. Some organizations like the Scientific Working Group on DNA Analysis Methods say that quantitative statistical evidence should be presented with every categorical conclusion, but the US doesn’t require this (Dror and Hampikian).

False Positives:

There are two categories that cause wrongful identification in a DNA report: coincidental matches and false positives. Coincidental matches are DNA matches between two unrelated people. The probability of these matches is about 1 to 500,000 for white individuals and about 1 to 350,000 for black individuals. This small probability of coincidental matches makes people feel confident in DNA evidence. False positives, on the other hand, are matches between DNA and test DNA that result from issues in the forensics lab. There have been multiple cases of forensics labs accidentally switching victim and suspected rapist DNA which lead to convictions that were later overturned when the lab realized the error. There are also cases of misreading or misunderstanding a sample. In a case from 1993, a man was convicted of rape because someone interpreted a mixed sample of victim and perpetrator DNA as an individual sample. The conviction was again overturned. To prevent false convictions, retesting DNA is allowed, but it’s not an efficient solution. Many people are pushing for statistical information on the probability of false positives, so that the jurors can make accurate judgements based on DNA evidence (Thomas et al.).  

Conclusion:

DNA analysis is a useful tool for the criminal justice system, but subjectivity can be an issue in forensic testing. To combat wrongful convictions, there are organizations like The Innocence Project who use DNA testing to free the innocent, but reformed forensic testing standards should be put in place to prevent subjectivity and to ensure juries are correctly informed during trials. https://www.innocenceproject.org/    

Citation:

Augustyn , Adam, et al. “DNA Finerprinting.” Encyclopedia Britannica , 26 Apr. 2018, www.britannica.com/science/DNA-fingerprinting#ref153186. Dror, Itiel E., and Greg Hampikian. “Subjectivity and Bias in Forensic DNA Mixture Interpretation.” Science & Justice, vol. 51, no. 4, 2011, pp. 204–208., doi:10.1016/j.scijus.2011.08.004. Jobling, Mark A., and Peter Gill. “Encoded Evidence: DNA in Forensic Analysis.” Nature Reviews: Genetics, vol. 5, no. 10, Oct. 2004, pp. 739–751., doi:10.1038/nrg1455. Thompson, William C, et al. “How the Probability of a False Positive Affects the Value of DNA Evidence.” Journal of Forensic Sciences, vol. 48, no. 1, Jan. 2003, pp. 1–8., doi:10.1520/jfs2001171.