March 21st is World Down Syndrome Day, part of a campaign to increase awareness of the genetic condition known as Down syndrome or Trisomy 21, which affects approximately 1 in 700 children, including our two-year-old daughter. While there still remains much to be done and to be protected in the future, the situation for people with Trisomy 21 is better today than ever before, beginning with early intervention programs and the opportunity to attend a regular school—parts of the IDEA (Individuals with Disabilities Education Act) civil rights law—and continuing with the opportunity to go to college, graduate, and get jobs.
Many parents of children with Trisomy 21 see World Down Syndrome Day as an opportunity to challenge stereotypes and lingering discrimination, to promote acceptance of children with Trisomy 21, and to highlight how much their children have in common with all children. However, while emphasizing that people with Trisomy 21 are more alike than different is centrally important, it can also be a double-edged sword by leading people to overlook the serious and unique medical issues that people with Trisomy 21 face.
These medical conditions stem from the genetic cause of Trisomy 21, which was first reported in 1959 by the French pediatrician Jerome Lejeune: a third copy of chromosome 21. Since then, scientists have tried to determine how this extra genetic material causes the medical issues that are associated with Trisomy 21. This research received a huge boost when, in 2000, chromosome 21 was fully sequenced, and scientists described the 225 genes they found on this chromosome (researchers have since identified more). With this knowledge, it became possible to draw concrete connections between these extra genes and specific medical issues, a process that is far from finished.
These studies show that the extra copy of chromosome 21 cause a wide-spread dysregulation of gene expression (the process by which the genetic code found in genes is turned into proteins usable by the body), not just on chromosome 21, but on others as well. As a result, numerous finely tuned biochemical processes that keep our bodies working are out of balance—sometimes there is not enough of a particular compound, sometimes far too much. One well-documented problem, for instance, is an overproduction of an enzyme (encoded on Chromosome 21) that makes hydrogen peroxide in the body—the same bubbling liquid used as a painful disinfectant for cuts. The enzymes that usually break this down, however, are not encoded on Chromosome 21; as a result, there is not enough of them to compensate for the overproduction. The result is a buildup, which in turn increases “oxidative stress,” contributing to early aging and degeneration, including loss of neurons in kids and a high rate of early onset Alzheimer’s-like dementia in adults.
Although oxidative stress can be treated, for instance using antioxidant compounds the body itself produces in insufficient quantities, most doctors do not know about this issue or the research on it. The outdated consensus persists that because Trisomy 21 is a genetic condition, treatment is not possible. In addition, many parents are unsettled by the idea of treating Trisomy 21, since for them it implies that something is wrong with their child. Many organizations that advocate for people with Trisomy 21, meanwhile, tend to distance themselves from discussion of treatment, focusing instead on social issues. But these reservations miss the point, which is that with today’s understanding and research, Trisomy 21, and the medical problems it causes, are in part treatable—and this has the profound potential to improve lives, especially if started early. It was, in fact, this realization that played a significant role in our decision not to terminate our pregnancy after our daughter was prenatally diagnosed with Trisomy 21.
A paradigm shift is urgently needed to bring this essential work to light, to fund more, and to promote its acceptance into medical practice. We know of no other medical condition for which there is such blanket acceptance that nothing can be done. It’s time to start a new effort to develop treatments for one of the most common genetic conditions—the decision to do nothing would be unethical and negligent, in contradiction to the Hippocratic oath.
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Update (March 26, 2017): We have updated this post by adding links to sources (there are many more), clarifying some language, and correcting some mistakes. We should also note, if this wasn’t clear from our by-lines, that we are not medical doctors, so nothing here should be misinterpreted as medical advice. Our view on this topic comes out of our backgrounds in biology (genetics and cancer research) and the social study of science and technology, as well as our experience as parents of an energetic girl with Trisomy 21.
We came to our perspective after growing weary of being told by medical doctors of all specialties that there is no research on the treatment of Trisomy 21, and that there is nothing, beyond the standard therapies, that can be done. This began on the day of our prenatal diagnosis two and a half years ago, and sounded, to be perfectly honest, rather implausible. As scientists, our response was to start reading about Trisomy 21 so that we could see for ourselves what was, or was not, in the research. And while it may sound strange to say a scientific paper changed our lives, “Prenatal Treatment of Down Syndrome: A Reality?”, which was published just a few months before, did just that.
Since then, we have come to realize that doctors often confuse the fact that they do not know about research with the mistaken belief that there is no research. But if this can be excused, the lack of interest and dismissiveness that we have experienced from countless doctors about the idea itself, or learning more about it, is far more troubling.
The idea of a treatment is often interpreted as a personal attack against people with Trisomy 21, and some organizations are strongly against the very idea of treatment, for this reason. For them, suggesting that Trisomy 21 is something that should be treated seems to be counterproductive to the ongoing struggle against discrimination and stereotypes of difference. While we can understand this point of view, and while we actively participate in this struggle every day, we think that the belief that Trisomy 21 is not a medical condition, in need of research and improved care, flies in the face of a growing body of knowledge. We take great risks in ignoring it.
Although sometimes perceived as such, our talk of treatments is not meant to suggest that anyone should change who they are. Indeed, we love our daughter as she is, unconditionally. At the same time, we try to separate who she is, from what she has. What she has is a third chromosome 21 that causes her body to do things differently than the bodies of people with only two. We highlighted one of those differences in the original post, but there are others, too. (In addition, not everyone with Trisomy 21 has the same issues, but some are often shared.) These differences matter because the human body is a complex system, and while scientists are just beginning to understand it, we do know that even slight perturbances can have significant consequences.