Stem cell therapies as potential reversers of hearing loss hit the news in a big way today when the UK's University of Sheffield announced that gerbils deafened as part of study can now hear after being treated with embryonic stem cell transplants. So what are stem cell therapies, how do they work, and what do they mean for the future of deafness in our society?
The Facts:
Stem cells are cells that have the capacity to self-renew and differentiate into a variety of different types of cells. They are often likened to a "blank slate" cell, as scientists can, using genetic and hormone markers, guide the cell into developing a certain way. There are two main types of stem cells-- embryonic, and adult stem cells. Embryonic stem cells come from embryos, that is from unborn children. Adult stem cells are inside our bodies right now, though they are already partially differentiated. For example, we have neural stem cells in our brains, capable of regenerating and differentiating into any type of brain cell, but probably incapable of differentiating into, say, a lung cell. Embryonic stem cells, on the other hand, are pluripotent, meaning they have the capacity to develop into all types of cells, (being as an embryo naturally does develop into a baby with all types of cells.)
There are currently many studies on the use of stem cells for hearing loss, but the one in the news today utilizes embryonic stem cells to regenerate auditory nerve cells in deafened gerbils. The embryonic cells used were human, and gerbils were used in the experiment because they have a similar hearing frequency and decibel range as humans. Marcelo Rivolta, the lead author on the study, said the therapy could be ready for human trials in "a few years." The time lag here in the United States may be longer, though, depending on the government's ever-contentious controls on the use of embryos for scientific research. To read more about Rivolta's study, click here.
The Good:
Stem cell therapy has the potential to cure a lot of devastating degenerative illnesses, including Huntington's, MS, and Parkinson's disease, so the more we know about stem cells and how to use them, the more advanced medical treatments will become. With regard to deafness, stem cells offer a way to repair auditory nerve damage, a type of deafness that cannot be treated with cochlear implants or hearing aids.
The Bad:
Potential issues with the use of stem cell therapies on humans include the tendency for stem cells to develop tumors, and the possibility that the patient's body might reject the implanted cells as foreign objects. Additionally, the long-term effects will remain relatively unknown until we can see the first generation's reaction to the treatment over a lifespan.
Additionally, stem cell therapy to treat hearing loss can and will have a very large effect on the Deaf Community. Firstly, the number of Deaf people is bound to shrink rapidly as the first few generations of children are transplanted; the transplants will likely take place in a child's infancy, possibly even using the stem cells found in umbilical cord blood. Such a child will be "fixed" before he or she is cognizant of being deaf. He or she will never have knowledge of or the choice to be a part of the Deaf community.
I'm of the mind that parents should be able to make decisions about what is best for their own children, and so cannot advocate for taking away that choice. That's not to say that the decision won't have a huge impact on the rest of us, though. What will happen when, in 20, 40, 60 years, the overwhelming majority of children born deaf have been "cured" within their first months of life? Will choosing to remain Deaf be stigmatized, or even possible? Will the government continue to support Deaf people through the ADA and other means if deafness is suddenly looked upon as optional?
If Deaf people are eventually eradicated, it will mean a huge blow to American diversity, the loss of a complex language and rich culture. (I say this not out of a bias toward Deafness, but rather as I'd judge the loss of any language or culture spoken and practiced by millions of people a blow to cultural diversity.) It's still a long way off, but not far enough away to ignore. I don't think it's wise to take a reactionary stance and stand in the way of scientific advancement. Here's hoping that a balance can be struck.
What do you think about stem cell research, and its potential socio-cultural implications?
I'm stepping outside my own worldview as a culturally deaf person and considering the issues you raised as objectively as I can. My first thought is that a cure for deafness via stem cells (assuming they are effective) is not a bad thing. for the majority of parents it will be a matter for rejoicing. As for it being "a huge blow to American diversity, the loss of a complex language and rich culture," not so much. it will be a huge loss to ME personally because after all, it's MY language and MY culture. but I feel the general American populace isn't even aware of us most of the time and will be unconcerned. I've long felt that the general public doesn't understand us and doesn't particularly want to. Leaving aside all protests of our uniqueness, value, beauty, etc., being hearing is the norm. I can see the population of culturally Deaf people becoming smaller with each generation until they are all gone. it's regrettable, but probably inevitable.
ReplyDeleteWith the ability to “cure” deafness by stem cells or direct genetic manipulation comes a larger question. Once the “genie is out of the bottle”, this can be applied to any number of other traits that parents might think undesirable. Parents will eventually be able to “cure” their infants of being black, Asian, blonde, short, tall, homosexual, left-handed, average intelligence – the list could be very long.
ReplyDeleteThe larger question is: What would the world look like if parents could choose and modify a large number of their child’s traits? Would we really think such a world is better than ours at present, or worse?
David
Wearing hearing aid shouldn't bother people but it's ironic when it obviously does when certain people run around screaming, "Hearies! Hearies! See?
ReplyDeleteThis is a good experience though. Thank you for the post!!