Breaking Blood: the discovery of Gwanda Negative
Do you know how many blood types are there? Have you ever thought how technology helps us with doscovering new knowledge? And it if happens instantly? This case will shed some light on the questions above.
The common belief is that there are eight common blood types; however, there are far more than this, although most of them are rather rare. Indeed, a 48th blood type was recently discovered in a woman from the French Caribbean island of Guadeloupe. During a routine pre-surgical blood test in 2011, clinicians in Paris noticed antibodies that didn’t match any known system. At the time, they did not have the appropriate tools to decode the mystery. But the sample was preserved, and in 2019, French researchers used advanced DNA sequencing to identify a rare genetic mutation that she inherited from both of her parents. They called it the Gwanda negative blood group (The Economic Times)
Discussion questions:
- To what extent do you think this is evidence that, in general, our classification systems in science change with the introduction of new technology? Does this mean that the categories we use are more a reflection of ourselves, our creativity and technological advancement, than actual types existing in nature?
- What makes one classification system better than another?
- Can we think of classification itself as being a kind of knowledge?
- How does the provisional nature of scientific knowledge influence public trust in science?
- To what extent can a single anomalous case change an established scientific consensus?
- Can we describe the increase in the number of blood types as scientific progress?
Commentary:
There are different views of classification systems (taxonomies) in science. Scientific realists think that the aim of science is to produce classifications that mirror as much as possible natural divisions that exist in nature: “carving nature at its joints”, as the saying goes. A better classification system will more closely mimic these natural divisions and, as a result, will have explanatory power. The problem with this view is that the example demonstrates that classification often depends on factors that are obviously human, such as the existence of technology or the appropriate concepts. It is difficult to divorce scientific investigation from the human. Scientific antirealists take the view that these human factors are really important and that human beings project their “humanness” on the world when they classify phenomena. For example, they are particularly interested in human blood groups because they are interested in what these groups tell us about the human immune system and the capacity to withstand disease. Because of these human interests, the antirealist is less convinced that these categories ‘really exist’ in nature.
If a classification system is used to explain phenomena in the world, then it seems reasonable to argue that it is itself knowledge.
Science is necessarily provisional. The idea that even fundamental concepts (like blood groups) can be revised underscores science’s provisional and self-correcting nature. People who, perhaps wrongly, regard scientific knowledge as absolute and unchangeable will be worried in situations where science changes its mind. However, those who regard science as being provisional will be encouraged by its openness to new evidence or new theoretical advances. Scientific classifications often reflect the limits of our tools; without the novel DNA sequencing technology, the Gwanda negative blood type would have been impossible to uncover. It shows that as technology improves, our knowledge grows, but this growth is often accompanied by an increase in the number of unanswered questions scientists face. Whether science progresses depends then on what you count as progress.
If you want to know more, visit our sites: Theories, laws, models, and assumptions, Challenges faced by the Natural Sciences and Progress in the Natural Sciences