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Turns out getting sick is bad for you. Go figure.

In the great to vaccinate or to not vaccinate debate, one of the most common arguments against vaccination (particularly when it comes to measles) is that it is better for your (or your child’s) immune system to fight off the measles naturally. After all, we were born with this immune system, let’s give it something to do right?

I can understand the tendency to default to a nature is better mentality. And I am often skeptical when we humans try to find an artificial shortcut to trying to improve on what nature has spent billions of years perfecting. So this question is worth asking. Is it better, or at least not harmful, to let our natural immune systems deal with the measles and avoid any discomfort you have over the vaccine? In a word, no.

A recent study has found that when you get the measles, you get more than just the measles. You see waaayyy back in the 60s, when kids started first getting vaccinated for the measles, not only did measles cases drop, but over all child mortality dropped too. At the time, people just shrugged their shoulders and said “Eh, let’s say it’s just good hygiene.” And it’s that same argument that people have used against vaccinations: the vaccines didn’t help us, better hygiene did.

Turns out, it was the vaccine. A postdoc at Princeton found that measles doesn’t just make you sick, it also gives your immune system amnesia. The immune system works by remembering what you’ve been sick with in the past, so if those germs show up again (or something that looks a lot like those germs) it recognizes them immediately and fights them off before you even get sick. In fact, the measles can keep affecting the immune system for 2-3 years.

It seems like usually when we discover an amazing cure-all, we end up find out 50 years down the road that it might not be the miracle we were hoping for (I’m looking at you DDT, artificial sweeteners, etc.). But it turns out that the measles vaccine is actually better than what we had originally hoped for.

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Pretty sneaky Ebola!

I know I know, Ebola is just soooo last year. In fact, once it became clear that (shocker) the most of Americans had about zero risk of catching Ebola all public interest pretty much seemed to drop off, despite the fact that hundreds of people in Africa continued to be infected and killed by the virus.

But every once in a while it seems that an article pops up to remind us how weird and scary the Ebola virus is. In the past week we’ve found out that not only can the virus be transmitted through sexual intercourse with a male survivor, but it can also keep living in your eyes long after it was cleared from the rest of the body.

To me, this is interesting because it’s introducing me to things about our immune system I never knew before. Like apparently the testicles have a less active immune system compared the rest of the body (fun fact, there is an entire field of study dedicated to the immune system within the testes called testicular immunology). Turns out, we have several areas in our bodies where antigens (basically things that don’t belong in your body) can be tolerated without causing an immune response. These areas are said to have immune privilege. These lucky little body parts can basically do whatever they want without fear of incurring the wrath of the antibodies, usually for good reason. In the testes this suppressed immune system is due to the fact that a male’s antibodies don’t recognize sperm and will attack and destroy them. And can you imagine if your body staged a full-scale attack every time you got a piece of dust in your eye? But, as is usually the case this privilege comes at a cost. If you turn off your security system it makes it a whole lot easier for the bad guys to get in, like Mr. Ebola.

But not all viruses need to find a weak spot to get past the body’s security guards. HIV for example is the master of disguise. This virus is so sure of itself it hides in the immune system itself. So sorry Ebola, you keep trying to be the most bad ass virus on the planet, but it looks like you still have a little work to do before I’m willing to dub you destroyer of all man kind.

Why are we OK with one gene manipulation study, but not another?

Last week a huge stir was caused when Nature reported on a Chinese paper which described a new technique which could be used to alter the genes in a developing human embryo. As stated in a Science news article, the aim of the paper was said to alter a mutated gene to prevent a blood disorder, and despite the fact that the technique actually didn’t really work very well there was an ethical uproar. In fact, both Nature and Science, the most prestigious journals in the industry, refused to publish the paper on ethical grounds. Many researchers have demanded an end to this line of research.

Just a day before Science published their news story describing the ethical backlash to this human embryo gene editing paper, they published another story. In fact, it was on a subject I have talked about here before.  A lab in San Diego is working on techniques to edit the mitochondrial DNA of an embryo to prevent disease. Sound familiar? But while there is a brief mention of safety and ethics (one sentence to be exact), for the most part this study is presented as a promising new technique.

So why are these two studies being treated so differently? Is it because the Chinese study was actually done on human embryos, while the second study has only been done on mice? This doesn’t make much sense to me, if a technique is being designed with the intent of eventually being used on humans, it should be the technique called into ethical question, not whether it’s being done on human or mouse (the human embryos in the Chinese experiment where embryos that would not have survived anyway due to other, more drastic genetic mutations).

Of course, when we talk of gene editing there is always the Gattaca fear, that the rich will be able to get designer babies and the gap between the rich and the poor will be cemented genetically as well as financially. And so it is understandable why people would get a bit fussy if we start perfecting those techniques, even if it is with the intent of preventing horrific diseases. But here’s what I don’t get, the Chinese technique didn’t even work. The San Diego technique did. So shouldn’t we be freaking out about the one that worked even if it was done on mice, since the plan is to do it on humans next? Maybe it’s because the work is done on mitochondrial DNA, which has nothing really to do with your physical appearance. But still, what can be done with one type of DNA should be pretty easy to jump to the rest of our DNA.

And should we be freaking out at all? I’m not about to go supporting paying a little extra to change your embryo so your kid can be faster, stronger and smarter. But I am a huge fan of having the ability to change your embryo so you don’t have to watch your kid slowly die from a terrible disease.

Let’s all be a little kinder to the anti-vaxxers

The anti-vaccine movement has been getting more attention than ever after the recent measles outbreak starting in Disneyland. Most of this attention (at least what I’ve read) has been negative. Actually, negative is putting it lightly. Anti-vaxxers are being burned at the stake for ignoring science and putting other children at risk due to their belief in unproven conspiracies.

And I admit, this was my first reaction too. When I first found out there were people in the world who chose not to vaccinate their children (which I didn’t even know was legal) I too found it idiotic. But now I feel that I, and the rest of the world, have treated these people unfairly.

First let me say that I in no way agree with or condone the anti-vaccination movement. Vaccinations have saved the lives of countless people and no one has ever proven any side-effects that are worse than the diseases they prevent. But I was raised in a home where vaccines were a given, and more importantly I was raised to trust science.

This should be no surprise to anyone, since I grew up to become a scientist. I have been trained to believe the results of experiments, and to trust the honestly of my fellow scientists. But, in the words of the great Dr. Gregory House (yes, I even trust fictional doctors), everybody lies.

Wakefield lied when he said vaccines cause autism. Then again, the FDA apparently covers up fraud in many drug trials. If you’re a concerned parent with no scientific background, what do you do?

You take the option with the smallest chance of risk. In science we call this risk aversion. Now, as a parent in today’s society, what seems like a bigger risk; a disease that was practically wiped out decades ago, or a developmental disorder that seems to be getting diagnosed more everyday? And it’s true that as long as a large enough percent of the population gets vaccinated, the odds of a few unvaccinated people getting sick are very low. We call this herd immunity. But as anti-vaccine beliefs grow in popularity, our herd immunity shrinks and the diseases crop back up again. And since they’ve been gone so long, many people have little or no experience with them and may think them to be more harmless than they are.

Now here I could throw a bunch of websites at you saying that immunity from vaccines is better for you immune system than getting the disease, or tell you how awful the measles are (or any other disease with a vaccine), or how there are no long-term side effects to getting vaccinated. But anyone pro-vaccine will already agree, and anyone anti-vaccine will point me to another website that says the opposite with a grand “well what about this?”

That “what about this” is where I have my biggest sympathy with the anti-vaxxers. Because those “what about this” websites are clever. They take bits of truth and weave them in with their lies. They play into the fears you already had and tell you what you want to hear to make those fears go away. And to the untrained eye they look so credible.

So no, I don’t think all anti-vaxxers are evil, and I don’t think they are all idiots. I think that, for one reason or another, they have lost their faith in big science. I can’t say I completely blame them. But I do want to change that. So if you ever talk to someone who is anti-vaccine (or anti-climate change, or anti-insertyoursciencehere), don’t call them an idiot. When was the last time you found someone calling you an idiot to be a persuasive argument? Don’t spit back the same generic proving it with science argument. Instead, ask them why they don’t believe in it. Find out what it is about science they distrust, and work forward from there. Because until we can inoculate them against whatever is driving their anti-science beliefs, we’ll always just be treating the symptoms.

(see what I did there?)

Autistic or anorexic, what’s the difference?

I read a fascinating article today that brought to mind a lot of questions about the nature of mental illness. The article’s title, “What it’s like to have anorexia and autism” featured on slate.com was so bewildering to me I just had to click on it. It is presented in an interview format, and features a woman named Sharon DaVanport who was diagnosed with anorexia when she was 17. At 42, she was diagnosed with Asperger syndrome, which is a higher-functioning type of autism. This made sense to Davanport, since her weight was not due to body-image, but rather to an aversion to food on a sensory level. She would be repulsed by the way some foods smelled or felt, to the point where she could not eat. This might not even be that uncommon of a case, as the slate article cites an article exploring a possible genetic link between autism and anorexia.

But when I first read this article, my initial thought was, but is this really still anorexia? Isn’t this more of a side effect of an entirely different disorder? The way DaVanport’s anorexia is described in the interview does fit in at all with the image I have of anorexia in my head. Anorexia has always been portrayed as an obsession to be thin that results in the individual being unable to view themselves as they truly are. For example, and woman with all her rib bones visible still believing she has love handles. But since DaVanport’s weight had nothing to do with a desire to be thin, how does it fit in? It does not compute into the box I had built around the idea of anorexia.

According to allianceforeatingdisorders.com the DSM-V (the go-to guide for diagnosing all mental diseases. Helpful tip: if you happen across a copy do not try to diagnose yourself. This will only end badly for you and ironically, your mental health) criteria for diagnosing anorexia nervosa include restriction of energy intake relative to requirements leading to a significantly low body weight in the context of age, sex, developmental trajectory, and physical health. Intense fear of gaining weight or becoming fat, even though underweight.

I've got your spectrum right here. Photo credit F.RdeC

I’ve got your spectrum right here. Photo credit F.RdeC

Disturbance in the way in which one’s body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or denial of the seriousness of the current low body weight.

In this case, Davanport would seem to only fit the first criteria. So it would seem in this case that Davanport was misdiagnosed as a teenager, which sadly probably happens all too much since so little is understood about mental illness.

That being said, the study done on looking at the relationship between anorexia and autism (which,  as far as I could tell, is the only one of its kind), stated that teenage girls who had anorexia exhibited more autistic traits than those without anorexia. The researchers hypothesized that this might be due to the obsessive nature that autism tends to produce could get directed towards calorie counting and limiting food intake. So then, is this anorexia due to body image, or is simply the result of obsessing about the food itself? Then again, the mayo clinic states in its description of anorexia that it isn’t really about food at all, but is instead an “unhealthy way to try to cope with emotional problems.”

So I ask again, if you have autism and an extremely low body weight due to limited food intake, are you still anorexic? I ask these questions not because I want to undermine what these women go through, nor do I wish to express outrage at the physicians for not better diagnosing their patients. I ask because I’m curious, and because I’m not sure if these questions even have answers. Because mental health is unbelievably complicated, and it can be so tempting to put people into neat little groups because it’s easier. But that doesn’t mean it’s right. I think it’s also important to note that the women in the anorexia study weren’t even necessarily autistic, they just had traits on the autism spectrum. Does that make them autistic? I don’t know, I’m not a psychiatrist, but my guess is not necessarily. In mental health it seems like nothing is certain, which is one of the reasons I could never do it, and I commend those who do.

Mutation in gene reduces heart attack risk

You probably used to seeing headlines to the effect of “Scientists discover the gene for aggression!” or “Scientists have found the gene responsible for liking the color blue!” and usually these headlines are extremely misleading. Unlike what you were lead to believe in high school biology, everything about you isn’t controlled by just one gene. For example, there is no “tall” gene. If there were, there would only be three heights: tall, medium, and short. Obviously this isn’t the case. Now, there are some traits that are controlled by a single gene. For example, dimples are controlled by a single gene. Either you have the trait for adorable little dimples, or you are out of luck. This is called Mendelian genetics, named after the monk Mendel who figured out the inheritance of traits in pea plants. The creatively named alternative, non-Mendelian genetics, describes traits which are the result of interactions of multiple genes. Most human traits are the result of non-Mendelian genetics.

Which is why articles that claim they’ve found the whatever gene are usually not entirely true. These studies typically describe a gene they found that plays a role in determining that particular trait, but they are by no means entirely responsible. But I guess the headline “Scientists have recently found a gene that greatly contributes to such and such” is not as snappy and might not garner as many views. However, I am willing to take this risk. Now on to the actual point of this post.

Scientists have recently found a gene that greatly influences triglyceride levels, which are a major cause of many heart attacks. People with a mutation that destroyed the APOC3 gene were able to eat very sugary food and have no spike in triglyceride levels. To be perfectly honest, I tried to do research on what this gene does and why destroying it might lower triglyceride levels, but I did not understand a word of the explanation they gave in the paper. Regardless, the point is that other scientists who know a lot more about this than I do can use this information to possibly develop a drug that could recreate the effects of the mutation. If they were able to do this, then people with high triglyceride levels could take this drug and as a result be less likely to have a heart attack. And you don’t have to be a fancy scientist to know that heart attacks are bad.

Why does everyone on Game of Thrones die with their eyes open?

I am sure dear readers that you all, like me, are avid Game of Thrones fans. For those of you who aren’t in the know, Game of Thrones is an HBO show based on the books by George R.R. Martin. Both the books and the show are hopelessly addictive, and incredibly violent (the show a bit more so). I mean, it is some pretty absurd violence. I actually laugh out loud at the absurdity of it sometimes (not because I think violence is funny, but because they are super creative at finding ridiculous ways to make deaths as creative and gory as possible).

Anyway, back to the point of this post. For some reason, this season it really struck just how often characters on the show die with their eyes open. Seriously, I haven’t crunched the numbers (cause I have a life, sorry) but I’m willing to bet the large majority of characters we see die still have their eyes open. And it’s not just Game of Thrones, this seems to happen a disproportionate amount in TV and movies. Now I understand, this makes a death more shocking and disturbing because people who are dead are supposed to look like they’re sleeping and eyes open makes them look haunted or like they could still be alive. But it did get me wondering, exactly how common is it for someone to die with their eyes still open? So I did some digging.

Turns out, I’m not the only one who’s been curious about this topic. In fact, a study in 2009 sought to answer this exact question. They only looked at 100 people, but would you really want to sit there and watch more than 100 terminally ill people take their last breaths? They discovered that 63% of patients died with their eyes fully closed. Those who died with their eyes open were much more

I refuse to show a picture of the GOT death I alluded to because looking at it creeps the hell out of me, so here's my adorable puppy instead.

I refuse to show a picture of the GOT death I alluded to because looking at it creeps the hell out of me, so here’s my adorable puppy instead.

likely to have some sort of neurological problem, like a brain tumor. They found no relationship between dying with eyes open and any sort of recent emotional turmoil or religious affiliation, so just because someone dies with their eyes open don’t automatically assume they were a devil worshiper.

Now unfortunately they did not also do a study on the likelihood of dying with your eyes open if the cause of death was disembowelment. Insert joke about the difficulty of finding volunteers here. So I still do not know how realistic those deaths are. But in the case of say, poison, which could potentially do severe neurological damage, then it wouldn’t be too far-fetched. But from now on, if I see any character die with his/her eyes open, I’m just going to have to assume they had some sort of brain tumor and therefore wouldn’t have lasted much longer anyway.