The recent rapid development of CRISPR technology, which has made gene editing fast, affordable, and accurate, has rekindled the ethical debate about human gene editing. Last week a special panel put together by the National Academy of Sciences gave a “yellow light” to human germline gene editing – saying that such editing might be ethical once the risks were properly assessed.
Germline editing means that the changes would be part of the gametes, the sperm or egg, and would therefore be passed down to offspring. If gene editing were done to a fertilized then this would affect all cells, including the germ cells.
By contrast somatic cell editing would affect only adult cells and not be passed down to the next generation. Such editing would only affect the individual.
The ethical controversy over germline editing is that such changes essentially can become a permanent part of the human population.
What Changes are Acceptable?
The NAS report essentially lays out two criteria for human germline editing. The first is that research shows that such editing is safe in humans without any unintended consequences. They want to make sure that dangerous changes to the human genome will not enter the human population. This is, of course, a perfectly reasonable criterion.
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In a recent article for Slate, Jacob Grier argues that the science used to justify widespread bans on smoking in public places was flawed. Recent more robust research has show little to no health benefit from such laws, he argues. While he has a point regarding the arc of scientific evidence, I think he is going too far in the other direction in his conclusions about the science.
Second Hand Smoke
The current consensus of evidence is that there are health risks to second hand smoke, although they are statistically small. Debate centers around the magnitude of the effect, with few doubting that there is a negative health effect. Negative health effects include heart attacks, lung cancer, stroke, and exacerbation of asthma. On a population level, even small increased risks result in large numbers of excess deaths and negative health outcomes. The CDC estimates, for example, that second-hand smoke exposure results in 34,000 excess cardiac deaths each year.
Increased recognition of the health risks of passive smoke exposure lent significant political weight to anti-smoking efforts, resulting in a cultural shift over the last 30 years. As a result smoking has largely been banned in most indoor public places and many work places.
The empirical question on which Grier focuses is the impact of those smoking bans on health outcomes. He does a fairly thorough review of the literature, although I think his review is biased to make his point, that the health benefits of such bans have been overplayed and maybe don’t exist.
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We have an anti-vaccine president. One of my concerns about Trump the candidate was that one of his most consistent positions over the years was blaming vaccines for the alleged autism epidemic (there isn’t one, by the way). Once elected it did not take long for this to manifest as a policy priority. In January Trump met with RFK Jr. to discuss him heading an Orwellian commission on vaccine safety and scientific integrity.
At a recent meeting with educators, Trump continued to express his false belief in a “tremendous increase” in autism:
“Have you seen a big increase in the autism with the children?” Trump asked Jane Quenneville, the principle of a Virginia public school that specializes in special education. Quenneville responded that she had.
Trump continued: “So what’s going on with autism? When you look at the tremendous increase, it’s really such an incredible — it’s really a horrible thing to watch, the tremendous amount of increase. Do you have any idea?”
“The autism?” Really? Continue Reading »
John Ioannidis has published an interesting commentary in JAMA about the current reproducibility crisis in basic and clinical scientific research. Ioannidis has built his career on examining the medical literature for overall patterns of quality. He is perhaps most famous for his study showing why most published research findings are wrong.
The goal here is to improve the science of science itself (or “metascience,” like “metacognition”). As science has progressed a few things have happened. The questions are getting deeper, more complex, and more subtle. Research methods have to be more rigorous in order to deal with these more subtle questions.
The institutions of science have also grown. Science is big business, which means that there are “market forces” which push institutions, scientists, and publishers into pathways of least resistance and maximal return. These pathways may not be optimal for quality research, however.
The stakes are also getting higher. We now have professions and regulatory schemes that are supposed to be science-based. If we take medical products, for example, the public is best served is products are safe and effective and truthful in the claims made for them. We need scientific research to tell us this, and we need to know where to set the bar. How much scientific evidence is enough? We can only answer this critical question if we know how reliable different kinds of scientific evidence are.
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Does legal or illegal immigration increase crime? That is an empirical question that should be answerable through rigorous research. Whatever the answer, it should inform our policy priorities and decisions. At the very least, if we are going to have a national conversation about immigration, the established facts should serve as common ground.
When you are done laughing (or crying) you might be interested to read about recent research into the correlation between patterns of immigration and various types of personal and property crime. Researchers have previously looked at this question by focusing on individuals – are immigrants more or less likely to commit crimes than native born Americans? Let’s consider that question first.
The research overwhelmingly shows that first generation immigrants, whether legal or illegal, are less likely to commit all types of crime at all ages than the native born. Interestingly, by second generation the statistics look more like native born crime rates, so it does not take long to assimilate in this regard. As an aside, this, of course, does not include crossing the boarder illegally itself, but it has been pointed out that being an undocumented immigrant is not a criminal offense, but a civil offence.
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H. Sterling Burnett, writing for the Heartland Institute blog, wrote a revealing post titled: Energy Restrictions, Not Climate Change, Put Civilizations at Risk. In my opinion it is a classic example of misleading propaganda, worthy of deconstruction as a case study.
What Is Propaganda?
I always endeavor to be as clear, thorough, and fair in my writing as possible. I am not saying I always succeed, but that is my goal. I have been influenced by my scientific background where clarity and accuracy rises to the level of obsession in the technical literature. It’s not possible to achieve that level in a non-technical blog, but it is a good ideal.
Propaganda is the opposite of clear, thorough, and fair. The purpose of propaganda is to persuade the reader to an ideological or political opinion, or to impugn or cast doubt on other people or other ideas. Being persuasive in an of itself does not make communication propaganda. In order to rise to that level there has to be a willful distortion of facts, a selective use of arguments and information, and the marshaling of any points that suit your ends, regardless of how fair they are.
Propaganda, like pseudoscience, exists on a spectrum. This further means that there is a demarcation problem – there isn’t going to be a bright line beyond which communication is clearly propaganda.
Burnett’s article shows multiple dramatic examples of what constitutes propaganda, and so should serve as an instructive example. This is not surprising since The Heartland Institute is an ideological think tank. They are not a scientific organization. Continue Reading »
Full disclosure – I have been a Patriots fan since in the 1980s. I suffered through a couple long decades of rooting for a mediocre team, including the worst (at the time) Super Bowl defeat at the hands of the Bears. Then along came Belichick and Brady, and it has been a wild ride as a fan.
Super Bowl LI was perhaps the pinnacle – the Patriots came back from a 25 point deficit to tie the game and then win in sudden-death overtime. I feel genuinely bad for Falcons fans, but perhaps worse for those who stopped watching the game in the third quarter because they thought it was over. Those who stayed through to the end were rewarded with historically epic football.
(As an aside, I am a fan simply because it is fun to have a team to root for. Don’t read too much into it.)
What is interesting, from a critical thinking perspective, about the game is the way in which we construct narratives to explain random events, or at least events that have an element of randomness or “luck” involved. At half-time the Falcons were up 21-3 and the discussion among the commentators was all about how well the Falcons were playing and everything the Patriots were doing wrong. The Falcons had “momentum” and the Patriots had to figure out a way to steal this elusive “momentum” back.
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Right now there are no genetically modified (GM) cultivars of wheat that are approved and on the market, so essentially there is no GM wheat. Wheat is an important staple crop responsible for about 21% of total calories consumed by humans in the world. Improving net yields of wheat could therefore have important impacts on our food production.
Over the last century agricultural experts have used conventional breeding, including hybrids, to increase yields of major crops. Apparently conventional breeding is running up against diminishing returns, and some believe we are at or approaching the limit of wheat yield with conventional techniques.
However, improving the efficiency of photosynthesis, the process by which plants turn sunlight into biomass, is an unexploited strategy. Researchers are now applying for field trials of a GM variety of wheat that incorporates genes from a closely related grass, the stiff brome.
Professor Christine Raines, Head of the School of Biological Sciences at the University of Essex and principal investigator for this research project, described the current modification:
“In this project we have genetically modified wheat plants to increase the efficiency of the conversion of energy from sunlight into biomass. We have shown that these plants carry out photosynthesis more efficiently in glasshouse conditions. One of the steps in photosynthesis shown to limit this process is carried out by the enzyme. sedoheptulose-1,7-biphosphatase (SBPase). We have engineered GM wheat plants to produce increased levels of SBPase by introducing an SPBase gene from Brachypodium distachyon (common name stiff brome), a plant species related to wheat and used as a model in laboratory experiments.”
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In Daniel Dennett’s latest book,From Bacteria to Bach and Back: The Evolution of Minds, Dennett explores a number of issues surrounding consciousness. I have not yet completed the book and so may come back to it again, but wanted to discuss one topic that Dennett covers – why are we conscious in the first place?
Dennett makes a distinction between competence and comprehension. Competence is the ability to perform some task, while comprehension is understanding the task and the process. The former is unconscious, while the latter is conscious.
This touches on Chalmers’ “P-zombie” problem – if we can imagine an organism that can do everything a human does without experiencing its own existence (a philosophical zombie), then why did consciousness evolve at all? There are several possible solutions to this problem. The first is that humans were “designed” to be conscious by whatever agent made us. This introduces unnecessary elements and contradicts established science, so I think we can set that aside.
The second solution is that consciousness is an epiphenomenon. We don’t need to be conscious, but we evolved consciousness as an evolutionary accident. This may be true, but is unsatisfying as it just side-steps the question of what use is consciousness.
The third solution, which I find compatible with the evidence and compelling, is that consciousness is inherent to the functioning of our brains and brings with it specific advantages.
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Pew recently published a survey looking at the attitudes of Americans regarding the safety and effectiveness of vaccines. The results are not surprising, but there are some interesting bits in the data.
The headline main results are that 88% of those surveyed thought that the benefits of vaccines outweigh the risks, while only 10% thought the risks outweigh the benefits. Further, 82% supported mandatory vaccinations for healthy school children.
This is both good and bad news. It means a solid majority of Americans understand that vaccines are safe and effective. However, the minority who doubt the safety of vaccines are enough to cause problems. Also, those numbers are a bit worse when you dig into the data.
Parents of young children, age 0-4, were more negative about vaccines, with only 81% stating that the benefits outweigh the risks, compared to 91% of those with older children and 90% of those with no children. Parents of young children are the ones deciding if they get vaccinated. The reason for this is likely that parents with young children are facing the decision of whether or not to vaccinate and are looking for information online. They are therefore more likely to come across anti-vaccine propaganda. Parents of young children may also be easier to scare than more experienced parents.
These numbers are important because of herd immunity – if enough of the population is vaccinated, then a disease outbreak cannot find enough susceptible hosts to spread and will therefore peter out quickly. This will keep the disease from being endemic, meaning that it is self-sustaining in the population. Continue Reading »