Wednesday, September 24, 2014

6 Things You Need To Know About Your Microbiome

You are not just a person – you are an ecosystem. Your body is home to trillions of microscopic critters, including viruses, bacteria, and fungi, living on or inside you. Collectively, these communities of microbes constitute what is called your “microbiome”.

And there are more of “them” than “you” – the number of microbes inhabiting your body is larger than the number of cells making up your body! To put this in perspective, it has been estimated that your microbiome weighs about 3 pounds. Good news if you’re on a diet – when you step on the scale tonight, feel free to subtract 3 pounds of stuff that isn’t “you” per se.

A new study concerning our microbiome seems to be coming out each week, so it is time we get to know our microbial roommates.

1. Where does your microbiome come from?

We are born virtually sterile, but quickly receive an infusion of bacteria from our mom, first through the birth canal and then through the milk. Over 900 species of bacteria have been found in breast milk, and these are the pioneers that settle into your gut, which appears to stabilize by the age of 3. Of potential interest are babies born by caesarean section or those who are fed formula instead of breast milk. Babies delivered via C-section do in fact have a different microbiome and may be at higher risk for certain types of allergies and obesity (more on this below). Our microbiome continues to receive fresh new imports as we move through, inhale, and ingest our environment.

How much of you is really you? There are more microbes in your body than the number of cells making up your body. We are just now beginning to appreciate the many things they do for us.
2. Your microbiome is like your own personal “germ cloud”.

You’ve probably noticed that everyone’s home smells a little different. Sometimes this is due to cooking, pets, or the amount of trash they let accumulate, but it is also due in part to the microbiome of the inhabitants. Researchers have found that you are surrounded by a “germ cloud”, and you leave pieces of your microbiome wherever you go like a trail of breadcrumbs. It might even be possible for police to use microbiomes to track people one day like they currently use fingerprints or DNA. In other words, you have a “microbiome fingerprint” that is left behind like a germ echo wherever you go.

This “germ cloud” may also explain how dogs can track people so easily. The byproducts generated by the millions of bacteria living on your skin are aromatic (odorous), producing a scent that is released into the air as you move. Animals with a keen sense of smell can get a whiff of these aromatic compounds and follow them to the source.

Speaking of “germ clouds”, if you ever wondered if it is possible to fart out germs, some brave scientists have sniffed out the answer to this question. You can read about the results here.

3. Antibiotics substantially alter your microbiome.

We take antibiotics to get rid of pathogenic bacteria that make us sick. The problem is they are not selective, so they destroy a lot of our friendly bacteria in addition to the bad guy. We need these friendly bacteria to do all sorts of things – to name just a few:  they help us digest food, make vitamins, and build anti-inflammatory compounds.

Another important thing our microbial friends do is keep infections in check. For example, yeast infections from pathogenic fungi can arise if good bacteria are not around competing for resources. And some bacteria, like the nasty Clostridium difficile, are naturally resistant to many antibiotics. When good bacteria are killed as collateral damage in an antibiotic treatment, the growth of Clostridium can run amok. These bacteria secrete a toxin that causes diarrhea and they can lead to a life-threatening superinfection in some patients.

4. Your microbiome may protect you from allergies or obesity.

Several recent studies have correlated unusual microbiome composition with the presence of certain allergies. Dr. Hans Bisgaard has shown that infants harboring fewer species of gut bacteria have an increased risk of developing certain allergies as they grow up. More recently, Dr. Catherine Nagler has shown that certain bacterial species offer protection from peanut allergies.

Dr. Martin Blaser has found that administration of penicillin to mice soon after birth altered their gut microbiome in such a way that it made them more prone to obesity as adults. Remarkably, the tendency to grow obese is transferrable to germ-free mice – in other words, by transplanting the microbes from the penicillin treated mice to normal mice made the normal mice more susceptible to weight gain.

Studies such as these make it tantalizing to speculate that we may be able to treat certain ailments in humans by altering our microbiome with specific probiotic regimens. Maybe they could even slip these bacteria into our peanut butter instead of deadly Salmonella.

5. How do scientists study the microbiome?

Advances in DNA sequencing have allowed scientists to rapidly map the genomes for many microbial species, which provides us with a “genomic fingerprint”. We can process samples swabbed from the skin or body cavities, or process stool samples, for DNA sequencing. Usually just sequencing the 16S ribosomal RNA gene is enough to distinguish one bacteria species from another.  

It should be mentioned that some scientists are issuing cautions about over-interpreting microbiome studies. Many of the studies altering the microbiome have been performed in mice, so it remains to be determined to what extent the findings can be extrapolated to humans. Furthermore, many of the methods used to alter the microbiome in lab animals do not faithfully mimic what humans do with antibiotics. For example, in some studies the investigators give large doses of antibiotics over unusually long periods of time to see an effect in lab animals, which does not equate to the typical dosing of antibiotics in humans. Finally, many of these studies are correlative and have not yet definitively demonstrated causation. There is a big difference between correlation and causation.

6. So should I take my microbiome into my own hands?

Much more research needs to be done to assess the true impact of the microbiome versus other factors that come into play, such as host genetics, diet, and the environment. It is argued that some microbiome studies are hyped up and way overblown. Long story short:  if you or your child becomes sick with an infectious agent, it is not wise to withhold antibiotic treatment out of fear that it will cause allergies or obesity. If you are overweight, a healthier diet and plenty of exercise is going to do much more than any probiotic pill. In fact, there is little evidence that the popular probiotics on the market do anything to remedy the wide-ranging health problems some claim to treat, although there is data showing potential benefit in treating some gastrointestinal maladies, especially acute diarrhea caused by rotavirus.

Go here to learn more about the NIH human microbiome project.

Contributed by:  Bill Sullivan, Ph.D.
Follow Bill on Twitter.

Lax S, Smith DP, Hampton-Marcell J, Owens SM, Handley KM, Scott NM, Gibbons SM, Larsen P, Shogan BD, Weiss S, Metcalf JL, Ursell LK, Vázquez-Baeza Y, Van Treuren W, Hasan NA, Gibson MK, Colwell R, Dantas G, Knight R, & Gilbert JA (2014). Longitudinal analysis of microbial interaction between humans and the indoor environment. Science (New York, N.Y.), 345 (6200), 1048-52 PMID: 25170151

Bisgaard, H., Li, N., Bonnelykke, K., Chawes, B., Skov, T., Paludan-Müller, G., Stokholm, J., Smith, B., & Krogfelt, K. (2011). Reduced diversity of the intestinal microbiota during infancy is associated with increased risk of allergic disease at school age Journal of Allergy and Clinical Immunology, 128 (3), 646-65200000 DOI: 10.1016/j.jaci.2011.04.060

Cox, L., Yamanishi, S., Sohn, J., Alekseyenko, A., Leung, J., Cho, I., Kim, S., Li, H., Gao, Z., Mahana, D., Zárate Rodriguez, J., Rogers, A., Robine, N., Loke, P., & Blaser, M. (2014). Altering the Intestinal Microbiota during a Critical Developmental Window Has Lasting Metabolic Consequences Cell, 158 (4), 705-721 DOI: 10.1016/j.cell.2014.05.052

Stefka, A., Feehley, T., Tripathi, P., Qiu, J., McCoy, K., Mazmanian, S., Tjota, M., Seo, G., Cao, S., Theriault, B., Antonopoulos, D., Zhou, L., Chang, E., Fu, Y., & Nagler, C. (2014). Commensal bacteria protect against food allergen sensitization Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1412008111

Williams NT (2010). Probiotics. American journal of health-system pharmacy : AJHP : official journal of the American Society of Health-System Pharmacists, 67 (6), 449-58 PMID: 20208051

Monday, September 22, 2014

Creating the Master Breed

They say that a dog is man’s best friend. But that isn’t how
the story goes. In 1870, a lawyer sued on behalf of a dog
owner whose foxhound, Old Drum, was shot by a sheep
farmer. His closing argument did explain why a dog is a
better friend than another person, but he never actually
said the phrase, “ a dog is man’s best friend.”
People heart their dogs – I read it on bumper stickers every day; apparently some dogs are smarter than my honor roll children. But for some reason, dogs haven’t caught on as viral video cuties to the extent that cats have. There must be scientific reason for that – you figure that out and win a Nobel Prize. I'm currently pondering the love of people for specific breeds of dogs; like it’s “the best breed ever” versus every other kind of inferior dog.

Our attempts to breed dogs with specific traits has had its drawbacks. Often, selective breeding of dogs leads to health problems.  Dogs bred to be big have a tendency to overheat, and the weight on their bones makes them more susceptible to bone diseases and bone cancer. Bulldogs have heads so big that they all have to be born by Caesarean section. Bassett hounds have immune system problems and blood dyscrasias - selective breeding has gone to the dogs.

A new study shows that health problems selective breeding in dogs may have a bright side. Chiari malformation occurs when the bones of the skull fuse too early and parts of the brain are forced through the base of the skull. It occurs in Griffon Bruxellois dogs at a shockingly high rate, but also occurs in humans.

One in 1000 people is afflicted with some degree of Chiari malformation (some are symptom free), yet the causes of this defect remain obscure. Studying the genetics in selectively bred dogs may help to identify genetic markers in humans.

Does this mean that all selective breeding is laden with problems? No - a relatively new dog breed called the Jagdterrier, or German Hunt terrier, is disgustingly healthy. Who do we have to thank for this marvel of selective breeding – the Nazis, oh great.

In the photograph on the left, Lutz Heck is shown on the far
left, while his best friend, Herman Goring, is on the far right
(no kidding).  Heck used his connections to fund several
selective breeding projects, including the production of the
German hunting terrier, the Jagdterrier, shown on the right.
The German national movement of the 1920’s and 30’s saw the rise of the Nazi party and the idea that anything German was better than anything else from anywhere else. And if being German is good, than being purely German must be better – even in dogs.

The hunting group of dogs at the time was well represented by the American Bloodhound and the four breeds of foxhound. Also at the time, terriers were at the height of their popularity. A terrier won the first Westminster dog show in 1907, and won eight of the first eleven shows.

So two brothers in Germany, Lutz and Heinz Heck, decided to breed a genetically and functionally superior German hunting dog, and to make it a terrier. Lutz was the curator of the Berlin Zoo and was no stranger to selective breeding in the name of German national pride, but more on that in a moment.

The two brothers were good friends with anyone high in the German government that they though they could suck up to. Lutz was very close to Herman Goering, and both brothers knew and were friends with Adolph Hitler. Hitler didn't fund their program as far as it is known, but the brothers used their connections in the Nazi party to procure patrons and partners.

The Heck brothers used the Welsh Terrier, the Old English Terrier and the Fox Terrier to start breeding toward the perfect hunting dog, but they needed the German blood, so they included a pinch of Pinscher and Dachshund as well. They wanted to end up with a dog that could run a fox to ground (chase it underground into its den), but was strong and nasty enough to take on bears. What they ended up with is the Jagdterrier, a breed finalized some years after the fall of the Reich.

Unfortunately, the German Hunting Dog was a victim of poor planning. We now have a dog that is too big to chase a fox into a den, but too small to take on a bear with any hope for survival. On the plus side, they don’t seem to have suffered from their selective breeding history – no health problems here, nothing to see, move on.

The Heck bovine on the left is the product of a selective
breeding program. Their map – the 10,500 year-old
cave painting on the right. How do you think they did? We
can’t know exactly how they tried because the Heck’s didn’t
keep a breeding book – very un-Nazi like.
Jagdterriers are good hunting dogs, but the one I know is crazy as a loon. I swear he’d eat my lawnmower if given the chance. They're a loyal and fierce breed, and this leads to quasi-terroristic behavior towards well-meaning neighbors. Thank you so very much, Herr Heck.

The brothers Heck didn’t stop there. They also used selective breeding to try and bring back an ancient cattle breed that wandered Europe a thousand years ago. Called the aurochs, this is the bovine immortalized in cave paintings across Europe – the supermodels of the Neanderthal period.

As opposed to the selective breeding of the Jagdterrier that was designed to a functional end, the breeding of the bovine was basically an attempt to generate an animal that looked like the picture; sculpting in live medium. A recent study has sequenced the aurochs mitochondrial genome using museum pieces, but my guess is that the modern day Heck Cattle, as they are called, will bear small genetic resemblance to the ancient breed.

For a guy who supposedly loved and worked with animals for conservation purposes, Lutz Heck turned out to be one nasty guy. In 1941, after the fall of Warsaw to the Nazis, Heck looted all the exotic animals from the Warsaw Zoo and took them back to Germany. For the remaining animals, he invited his SS friends to have a private hunt and slaughtered them in and out of their pens – a massacre. Not such a great advertisement for the Nazis, who claimed to be such advocates for animal rights.

Contributed by Mark E. Lasbury, MS, MSEd, PhD
As Many Exceptions As Rules

German Colonialism: Race, The Holocaust, and Post-War Germany. edited by Volker Max Langbehn, Mohammad Salama. New York, Columbia University Press, 2011.

The Zookeeper's Wife. Diane Ackerman. New York, W.W. Norton, 2007.

Lemay P, Knowler SP, Bouasker S, Nédélec Y, Platt S, Freeman C, Child G, Barreiro LB, Rouleau GA, Rusbridge C, & Kibar Z (2014). Quantitative trait loci (QTL) study identifies novel genomic regions associated to Chiari-like malformation in Griffon Bruxellois dogs. PloS one, 9 (4) PMID: 24740420

Zeyland J, Wolko L, Bocianowski J, Szalata M, Słomski R, Dzieduszycki AM, Ryba M, Przystałowska H, & Lipiński D (2013). Complete mitochondrial genome of wild aurochs (Bos primigenius) reconstructed from ancient DNA. Polish journal of veterinary sciences, 16 (2), 265-73 PMID: 23971194

Wednesday, September 17, 2014

Autumn Leaves: More Than Just Pretty Colors

This post originally appeared on the Telegram and Gazette 9/2012

The green tree leaves of summer are already starting to give way to the bright yellows and reds of autumn. We should have a brilliant display of colors throughout the fall.

As you may remember from your high school science class, what gives green leaves (and green plants in general) their color is a compound called chlorophyll, which absorbs light energy from the sun. As the summer comes to an end, the change in temperature and change in the amount of daylight trigger processes in the leaves that cause chlorophyll to break down. As this inducer of green color disappears, the color effects of other compounds, carotenoids and anthocyanins specifically, are unmasked. Carotenoids are the compounds that give carrots their orange color and bananas their yellow color. Anthocyanins can give plants bluish, purplish, or reddish tints. Red cabbage, cranberries, and red raspberries are just a few examples of produce that have high levels of anthocyanins.

For the most part, scientists thought that the changing of leaf color in autumn was simply an effect of the disappearance of chlorophyll and signaled that the leaves were about to fall.  Over the past several years, however, researchers have found that the appearance of yellow, orange, and red leaves may have additional ecological impacts.

In 2005, researchers Martin Schaefer and Gregor Rolshausen proposed that the changing leaf color actually acts as a defensive signal against consumption by herbivores (plant-eating organisms).  The "Defense Indication hypothesis," as they termed it, is based on their own work as well as on observations that support their ideas, but were made by other researchers.  Their hypothesis (or, idea that will be tested through experiments and observations) is based on the fact that the signaling pathway that causes the production of anthocyanins also causes the production of defensive compounds to which herbivores have an aversion. After enough time, it is thought that herbivores learn to associate the defensive compounds with the colored leaves and avoid them altogether.

The very hungry caterpillar ate lots of stuff, but not orange, red, or yellow leaves.
Further, the biochemical pathways that cause chlorophyll to break down become active along with pathways that cause the production of compounds called anti-feedants, which make the leaves difficult to digest. If herbivores repeatedly consume autumn-colored leaves and then become sick due to the anti-feedants, they learn to associate the red, yellow, and orange colors with a negative eating experience and avoid those colored leaves in the future.

While the primary cause of autumn leaf colors is the loss of chlorophyll, this paper discusses just one example of how the color change has a significant impact on other organisms. Like so many things in nature, one change often has the potential to ripple through the environment and bring about widespread ecological effects.

Contributed by:  Kelly Hallstrom
Visit Kelly’s blog, You Don’t Have To Be A Rocket Scientist
Follow Kelly on Twitter.

Schaefer HM, & Rolshausen G (2006). Plants on red alert: do insects pay attention? BioEssays : news and reviews in molecular, cellular and developmental biology, 28 (1), 65-71 PMID: 16369938

Monday, September 15, 2014

Sweating Is The Pits

It was in the late 9th century when some societies decided that armpits needed to be kept from fulfilling their stinky destinies. Some locales still haven't gotten the message. Deodorants and antiperspirants are meant to reduce the causes of axillary odor, axilla being the scientific term for armpit, but could we be doing more harm than good with them? Let’s find out.

What does this image have to do with armpits and deodorants?
Well, this is Ziryab, the inventor of the first known underarm
deodorant. He also made fashionable the idea of Muslim men
shaving their faces – still a matter of personal choice except in
some of the strictest sects. Ziryab was a scientist and an artist,
a polymath of the first degree – and maybe he developed the
first Degree (an antiperspirant – get it?).
A long time ago in the Islamic portion of Spain, a very smart guy name Ziryab invented what would later become the beauty aisles at CVS. He developed a deodorant for the axilla, a toothpaste for oral hygiene, bath salts for the skin, and oils and conditioners for the hair. This is only a little weird since he was really a musician and poet – although he had knowledge in astronomy meteorology and botany as well. Unfortunately, his inventions were lost and had to be reinvented later.

Mum was the first commercial deodorant marketed to reduce body odor from the armpits – it’s still around today under the name Ban. It was developed in Philadelphia in the late 1890’s, and became a commercial hit. Deodorants usually contain alcohol, acids, or triclosan, all of which kill or deter bacterial growth. More on that in a second.

Most deodorants also contain a masking fragrance, some perfume contained in a starch microsphere. When sweat breaks down the starch, it releases the fragrance. Starch spheres of different sizes means they breakdown after different periods of time in sweat, so they can keep you socially acceptable for longer periods of time.

On the antiperspirant side of the equation, Stopette was developed in 1941. Antiperspirants contain one or more of several aluminum compounds. Weird as it sounds, they work by combining with the ions in your sweat to clog up your pores so that you don’t sweat. Does that mean that prolonged use will force your underarms to swell from retained sweat until you explode and blow off both your arms. No- but it stirs up an interesting visual.

The function of deodorants/antiperspirants is to prevent you from offending everyone else due to the bacterial byproducts that buildup in your armpits as the day progresses. Bacteria are on your skin – all of your skin. In fact, you have more bacteria on your skin than you have skin cells. Like I said, a lot of bacteria.

Leonard Hofstader on The Big Bang Theory apparently
was stressing over his upcoming date with Penny. The
apocrine glands produce nutrient rich sweat with an
increase in stress hormones. They empty into the hair
follicles, as opposed to onto the skin directly for eccrine
glands. This is why some people shave their armpits to
reduce smell, the fatty products of apocrine glands stick
to hairs and promote more odor.
Your armpits (axilla in scientific terms) offer a warm, moist, food-filled cave in which bacteria thrive. You sweat to control temperature, and this sweat pours forth from the eccrine glands. There are also apocrine sweat glands that control emotional sweating, like when you’re stressed about that first date and all you have clean are royal blue dress shirts. 

Apocrine glands release water and salts like eccrine glands, but their sweat contains more fats, sugars and proteins – and this is food for bacteria. When you reach puberty, the number of these glands in the axilla increase greatly, up to 25,000-50,000 per pit. Apparently evolution has determined that kids don’t have anything to be stressed about.

Bacteria + bacterial food from sweat = bacterial growth and division. With more bacteria come more bacterial products. Basically, these products are chemicals that are produced as a function of bacterial metabolism – it’s their waste products, communication chemicals, and toxins that we smell later in the day.

This brings up an interesting point – well, interesting to me – deodorants suppress odor by killing bacteria and antiperspirants suppress bacterial growth by limiting their sweat-based food, and that then prevents the odor. So all antiperspirants are deodorants, but not all deodorants are antiperspirants. So that makes the products labeled as deodorant and antiperspirant just plain old redundant.

Actinobacteria produce some of the most foul smelling chemicals
associated with body odor. However, a subset of actinobacteria
called actinomycetes make a chemical called geosmin. This is
the chemical that gives the wonderful earthy smell after a rain.
We have discussed how deodorants/ antiperspirants help us, but new research is showing that they may have some drawbacks. A 2014 study in Belgium asked people to forgo their underarm cosmetic regimen for one month. The scientists found that there was a stable community of bacteria (number and types of bacteria = community) when using the products and a stable community when not using the products. But the bacterial communities were different in each situation, with more different types of bacteria seen in the unnatural condition.

In fact, more Actinobacteria were present when antiperspirants were being used, and these produce some of the foulest smelling by products. Therefore, we may be adding to our funk by trying to prevent it. Of course, everyone is entitled to their own crop of axillary bacteria, so differences were seen from individual to individual.

This is may be an unfortunate effect of antiperspirant usage, but there may be more important problems. All women are told not to wear deodorant or lotions when having a mammogram - but do you know why? We said that antiperspirants contain aluminum or zirconium, and we now know that these can stop X-rays from passing through tissue. They can look like small calcifications in the tissue of the breast, and this can lead to false readings of mammograms. That's bad enough, but they may contribute to breast cancer as well.

This is a mammogram image from a breast with cancer. The
main tumor is shown with a single arrow, and the associated
microcalcifications are shown with the double arrows.
Unfortunately, aluminum in antiperspirants can look just like
the calcifications, without or without underlying disease.
The evidence is far from conclusive, but certain studies have shown that the aluminum in antiperspirants can build up in the breast tissue over time. Other studies show that aluminum can stimulate estrogen-like hormone production, and estrogens are known to promote breast cancer cell growth. No studies have shown that antiperspirants cause breast cancer, but more study is needed.

A 2013 review discusses the various studies that indicate an effect of aluminum on breast physiology, including altered iron metabolism, increased oxygen radicals and increases in inflammation. On the other hand, another 2013 study found no difference in aluminum concentrations in normal and cancerous breast tissue, so the causative effect is definitely not proven.

On the other hand, antiperspirants don’t seem to interfere with radiation therapy for breast cancer. A 2012 paper indicated that aluminum based antiperspirants don’t affect the beams of radiation (much like X-rays) that are used to treat some early stage breast cancers. Antiperspirants might promote breast tumors, they do mimic how breast tumors look on X-rays, but apparently they don’t hurt the treatment once you already have breast tumors. Weird.

contributed by
Mark E. Lasbury, MS, MSEd, PhD
As Many Exceptions As Rules

Callewaert C, Hutapea P, Van de Wiele T, & Boon N (2014). Deodorants and antiperspirants affect the axillary bacterial community. Archives of dermatological research PMID: 25077920

Watson LC, Gies D, Thompson E, & Thomas B (2012). Randomized control trial: evaluating aluminum-based antiperspirant use, axilla skin toxicity, and reported quality of life in women receiving external beam radiotherapy for treatment of Stage 0, I, and II breast cancer. International journal of radiation oncology, biology, physics, 83 (1) PMID: 22516385

Darbre PD, Mannello F, & Exley C (2013). Aluminium and breast cancer: Sources of exposure, tissue measurements and mechanisms of toxicological actions on breast biology. Journal of inorganic biochemistry, 128, 257-61 PMID: 23899626

Rodrigues-Peres RM, Cadore S, Febraio S, Heinrich JK, Serra KP, Derchain SF, Vassallo J, & Sarian LO (2013). Aluminum concentrations in central and peripheral areas of malignant breast lesions do not differ from those in normal breast tissues. BMC cancer, 13 PMID: 23496847

Friday, September 12, 2014

The Friday Five

Highlighting some of the coolest science news we’ve seen lately.

1. The coffee plant (Coffea canephora) genome has finally been sequenced! Interestingly, the study revealed that the enzymes synthesizing caffeine evidently arose independently from others found in tea and cacao. The question that remains:  how many cups of coffee were required to get the data? Learn more, including why some plants make caffeine, in Carl Zimmer’s article. It took millions of years for plants to evolve the ability to manufacture caffeine, so it is no wonder we freak out when there’s no coffee:

2. Scientists were able to correct the genetic aberration in mice that causes muscular dystrophy using a new type of genome editing technique called CRISPR/Cas9. In the future, this strategy may be used to correct disease-causing mutations in the muscle tissue of humans. Learn more about CRISPR/Cas9 in the video below.

3. More big medical breakthroughs: one of the most promising medications for melanoma was fast-tracked by the FDA last week.

4. This doesn’t happen every day! Check out this live volcanic eruption and sonic boom of Mount Tarvurvur located in Papua New Guinea.

5. In a previous Friday Five, we highlighted a study on how to make the perfect pizza. So how about a little perfect dessert to go with that perfect pizza? Read on to discover the science behind the best chocolate chip cookie for you.

We recently wrote about species having names inspired by celebrities. Now we have a new one to add to the list. “A swamp-dwelling, plant-munching creature that lived 19 million years ago in Africa has been named after Rolling Stones lead singer Sir Mick Jagger, because of its big, sensitive lips and snout. The name of the animal, Jaggermeryx naida, translates to 'Jagger's water nymph.'”

Science quote of the week:
“The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.” –Isaac Asimov

Contributed by:  Bill Sullivan
Follow Bill on Twitter: @wjsullivan

Denoeud, F., Carretero-Paulet, L., Dereeper, A., Droc, G., Guyot, R., Pietrella, M., Zheng, C., Alberti, A., Anthony, F., Aprea, G., Aury, J., Bento, P., Bernard, M., Bocs, S., Campa, C., Cenci, A., Combes, M., Crouzillat, D., Da Silva, C., Daddiego, L., De Bellis, F., Dussert, S., Garsmeur, O., Gayraud, T., Guignon, V., Jahn, K., Jamilloux, V., Joet, T., Labadie, K., Lan, T., Leclercq, J., Lepelley, M., Leroy, T., Li, L., Librado, P., Lopez, L., Munoz, A., Noel, B., Pallavicini, A., Perrotta, G., Poncet, V., Pot, D., Priyono, ., Rigoreau, M., Rouard, M., Rozas, J., Tranchant-Dubreuil, C., VanBuren, R., Zhang, Q., Andrade, A., Argout, X., Bertrand, B., de Kochko, A., Graziosi, G., Henry, R., Jayarama, ., Ming, R., Nagai, C., Rounsley, S., Sankoff, D., Giuliano, G., Albert, V., Wincker, P., & Lashermes, P. (2014). The coffee genome provides insight into the convergent evolution of caffeine biosynthesis Science, 345 (6201), 1181-1184 DOI: 10.1126/science.1255274

Long, C., McAnally, J., Shelton, J., Mireault, A., Bassel-Duby, R., & Olson, E. (2014). Prevention of muscular dystrophy in mice by CRISPR/Cas9-mediated editing of germline DNA Science, 345 (6201), 1184-1188 DOI: 10.1126/science.1254445

Wednesday, September 10, 2014

Midi-chlorians gave Jedi knights their power. Is there something like this on Earth?

Star Wars Episode VII is happening, to the cautious delight of many longtime fans of the franchise. Replacing George Lucas at the helm is J.J. Abrams, who successfully rebooted the Star Trek franchise.

The cast for Star Wars Episode VII meeting with Yoda J.J. Abrams
Fans are waiting with bated breath to see whether he does a better job than Lucas did with the Star Wars prequels, which caused a great disturbance in the Force. While Jar Jar Binks soured the prequels for most people, one of the other sticking points was the Midi-chlorians. The what? Let's review. In the original series, the Force was described by Obi-Wan Kenobi as "an energy field created by all living things. It surrounds us, penetrates us, and binds the galaxy together." In episode I, Qui-Gon Jinn delivered the buzzkill message that the mysterious Force actually had a biological explanation. Instead of saying, “The Force is strong with this one”, one may as well say, “The Midi-chlorians are numerous in this one.”

According to Wookieepedia, “Midi-chlorians were intelligent microscopic life forms that lived symbiotically inside the cells of all living things. When present in sufficient numbers, they could allow their host to detect the pervasive energy field known as the Force.” A collective groan could be felt through movie theatres worldwide, as if millions of voices suddenly cried out in terror…

To a cell biologist, it sounds like Lucas drew his inspiration from the mitochondria, which are bacteria-like symbionts that work with our cells to provide energy. They even look like they might be cousins (see below). But that is where the similarities end. Unlike Midi-chlorians, mitochondria do not allow us to tap into energy fields…no matter how much we try to quiet our minds to hear our mitochondria speak to us.

Midi-chlorian (left) and mitochondria (right). Brothers from another mother?
But a strange and provocative paper by Alexander Panchin and colleagues proposes an unorthodox new idea called the “biomeme hypothesis”, which posits that the impulse behind some religious rituals could be driven by mind-altering parasites.

Let that sink in for a moment. Might your religion, or any number of other activities, be driven in part by parasites or symbionts in your brain? Before you dismiss the idea too quickly, think about the rabies virus. This super tiny virus is notorious for altering the behavior of dogs (and other animals, including people). Rabies can make even the most docile of dogs become uncharacteristically aggressive so that they bite and spread the virus. Rabies virus is just the tip of the iceberg; there is no shortage of parasites that are known to eerily alter their host’s behavior.

Rabies makes dogs aggressive to enhance viral transmission. The virus can get into a new host by causing its current host to bite others.
Central to Panchin’s hypothesis is the idea that certain religious rituals may facilitate the transmission and spread of parasites. The authors site that holy springs and holy water are replete with numerous microbes, including human pathogens. Sacred in Hinduism, the Ganges River probably contains the most, as an estimated 200 million liters of untreated human sewage is dumped into it every day. Bathing in this “purifying” water has led to the development of multiple diseases, such as cholera.  The Hindu “side-roll” ritual is associated with Cutaneous Larva Migrans, also known as “creeping eruption of the skin”, which is caused when the skin becomes infected with parasitic hookworm larvae. Performed in Muslim communities, ritual ablution, which involves irrigation of the sinuses, has been proposed to be a potential risk factor in contracting Naegleria fowleri (the infamous “brain-eating amoeba”) in Muslim communities. Outbreaks of respiratory infectious diseases and meningococcal disease are common amongst Hajj congregation in Mecca. The transmission of herpes has been reported in the Jewish circumcision method known as metzitzah, which involves the sucking of blood from the wound. Finally, many sacred relics are kissed or handled by many worshipers, offering additional routes for the potential transmission of multiple infectious agents.

While it is clearly demonstrable that certain religious rituals have inherent health risks, there currently is no direct evidence that any of the possible infections transmitted can influence the victim’s behavior (other than causing them to see a doctor). Until new data arrives, we are left with the conclusion that the rituals people engage in stem from cultural memes rather than biological. But one thing is clear:  you should use some hand sanitizer next time you dip your fingers in the holy water.

Contributed by:  Bill Sullivan
Follow Bill on Twitter
Panchin AY, Tuzhikov AI, & Panchin YV (2014). Midichlorians--the biomeme hypothesis: is there a microbial component to religious rituals? Biology direct, 9 (1) PMID: 24990702

Monday, September 8, 2014

I’ll Wager That You Bet On Football, Or Maybe Football

Opera diva Renee Fleming (left) sang the national anthem
at the 2014 Super Bowl. Millions of dollars were
wagered on just how long it would take her to get through
the Star Spangled Banner. Pop star Kelly Clarkson (top) took
only 1:34, so the smart bettors went with a longer time for
an opera singer. The over/under was 2:25, but she came in
a solid 35 seconds under that line. Alicia Keys (bottom), on
the other hand, took almost three minutes!
It’s fall again. The NFL season just began and across the pond the English Premier League soccer season has a few games under its belt. You know what that means – lots and lots of gambling.

Between American football and football proper, literally trillions of dollars are wagered each year. And that just counts the games, not the fantasy leagues. For all the readers in the US - yes there are indeed fantasy leagues for the English Premier League.

Each sport is the top betting sport in its respective country, unless you count the massive gamble that NBC took signing a contract to show the EPL in the United States. You can bet on just about anything that concerns the games; who'll get hurt, who'll score first, even the coin toss. In 2014, betting on the Super Bowl surpassed 100 million dollars, and only 42% of that was bet on who would actually win the game!

About 4% of those people who bet on at least a semi-regular basis will go on to develop a gambling addiction, or a “pathologic gambling” problem. There have been lots of study in recent years as to why people gamble, and why only some people develop an addiction. As with most things, it comes down to which is the chicken and which is the egg.

A recent study in Thai students showed that 20% of teenagers gambled, mostly on cards, but only slightly less popular was football (soccer). Ten percent of those who gambled were considered to be addicted. Since only 4% of adults become addicted, does this mean that children are more susceptible? Maybe, but it could be other things as well.

The authors found a strong negative correlation between education and gambling. As GPA went down or the level of education stayed low, the chance of pathologic gambling went up. But which is the cart and which is the horse? Do people with poor grades or education have more chance to become problem gamblers, or does problem gambling lead to poor grades?

More betting on World Cup and other football games has led
to an increase in Chinese, Russian, and North Vietnamese
hacking syndicates that prey on gamblers. Match fixing is also
becoming a big problem as more criminal enterprises try to
make a killing on the beautiful game.
The take home lesson, beyond that Thai kids apparently have too much spending money, is that correlation does not imply causation. Just because two things occur together, it doesn’t mean that the first causes the second or that the second causes the first. One or the other might be causative, but it doesn’t follow that one must cause the other.

So why do they gamble? Is it thrill seeking, for potential monetary gain, for social reasons? There may be as many reasons for gambling as there are gamblers, but some common issues crop up in pathologic gamblers.

Two terms used in the study of gambling are “illusion of control” and “near miss.” These seem to be especially important in football and football. Illusion of control is the feeling that knowing more about the game and being up on the latest data and statistics make a tangible difference in the outcomes of wagers. It ain’t so.

A couple of recent studies give us evidence to the futility of extensive studying. A 2012 study compared the result of choosing 10 soccer games. Professional football gamblers were compared to people who knew nothing about the game and to amateurs who followed the game casually. They all succeeded at comparable rates – knowing more about the game made no difference whatsoever.

This result was supported by a 2013 study that picked the round of 16 games in the European Champions League. Again, people who were ignorant of the game bet just as successfully as the pros. Nevertheless, pathologic gamblers do seem to believe that they have more control over the outcome of wagers, and this is one of the justifications they use to continue. The more they continue to study and bet, the more likely they will develop a problem.

A recent series of experiments shows that it is more complicated than this, at least for football (or football). Gamblers of many ages and betting frequency range were queried as to whether they believed in their luck or their skill for gambling. For football, frequency of betting related more to a belief in luck than their image of themselves as “in the know.” The results were different for casino games, where a sense of skill led to more frequent betting. So football betting isn't always about thinking you have an information edge.

These are MRI scans of the brain while betting on a slot
machine. The left image is a scan of the reward center activity
in a win, but they have subtracted the activity that occurs with
a loss. On the right, the signal during a win was subtracted
from the signal in a near miss situation. There is actually more
activity in a near miss than in an actual win! No wonder
people get hooked on betting.
The “near miss” is more interesting. Having your team lose by one point, or on a fluke play (something like the Fail Mary in the Seahawks/Packers game of 2012) is excruciating – but it's also more exciting, especially for pathologic gamblers. The feeling of excitement and payoff is bigger in these games than even in games that they might win.

In the above study, rats who were trained to press a lever for food after a random press light three lights, pressed the food bar just as often when only two lights were lit – even though pressing it for a non-win (three lights was a win) induced a time penalty during which they couldn’t play again. They knew it would bring a penalty, but the near miss still had some irresistable appeal for the brain’s reward center.

It’s a dopamine thing. Dopamine is a neurotransmitter in the brain that has a lot to do with reward – things that give our brains pleasure. About ten years ago, scientists noticed that people that were started on medicine for Parkinson’s disease (a disease in which motor coordination is impaired due to the loss of dopamine producing neurons in the substantia nigra of the brain) developed gambling addictions at much higher rates than the general population.

Dopamine works in different ways for different parts of the brain. When treating the basal ganglia (BG) that controls muscle movements with dopamine (the dopamine in the BG is low in Parkinson's), you are also increasing the dopamine levels in other parts of the brain. It isn't the treatment of the tremor that causes people to gamble, it's the inadvertent actions of the dopamine on some other part of the brain that leads to gambling problems.

For example, the “near miss” releases just as much dopamine in the reward centers of the brain as does a win and correlates highly with development of gambling addiction. Does too little dopamine mean that they have to gamble more than other people in order to get the same effect, and this is exacerbated by dopamine containing medicines? Maybe. Pathologic gamblers do seem to release more dopamine in the mesolimbic area of the brain (motivation control) when gambling than do healthy control subjects.

This cartoon illustrates just how difficult it is to prove a causal
relationship between dopamine and pathologic gambling. The
different areas of the brain use different combinations of
dopamine receptors, and these can change with disease or
trauma. Each are will react differently to too much or too little
dopamine, or to changes in other neurotransmitters that affect
dopamine activity or release. But scientists are good at isolating
variables, I bet we get it sooner rather than later.
However, a 2013 study showed that the motivational area dopamine areas had more dopamine when the reward (winning the bet) was uncertain as opposed to after it was won. This leads to the idea that there is more of a thrill in uncertainty and is itself the reward. When dopamine drugs enter the brain indiscriminately, these feelings are exacerbated, and more gambling is needed to keep the reward (pleasurable feeling) going.

Unfortunately, it's much more complicated than this. There are different types of receptors for dopamine on the different types of neurons. Too much or too little dopamine can over time change the number and types of dopamine receptors found on the neurons, so dopamine activity in a healthy brain isn’t exactly the same as dopamine activity on a previously dopamine starved brain. This is exemplified by a case report in 2013 of a patient who quickly developed a strong and uncontrolled gambling problem after beginning drugs to lower the dopamine levels in his brain.

So once again, we see that just correlating dopamine levels with gambling on football (or anything else) isn’t enough to say that it causes the gambling addiction. We know dopamine is playing a role, but is it too little or too much that leads to gambling addiction? Your bet is as good as mine.

contributed by
Mark E. Lasbury, MS, MSEd, PhD
As Many Exceptions As Rules

Anselme P, & Robinson MJ (2013). What motivates gambling behavior? Insight into dopamine's role. Frontiers in behavioral neuroscience, 7 PMID: 24348355

Huberfeld R, Gersner R, Rosenberg O, Kotler M, & Dannon PN (2013). Football gambling three arm-controlled study: gamblers, amateurs and laypersons. Psychopathology, 46 (1), 28-33 PMID: 22890307

Khazaal Y, Chatton A, Billieux J, Bizzini L, Monney G, Fresard E, Thorens G, Bondolfi G, El-Guebaly N, Zullino D, & Khan R (2012). Effects of expertise on football betting. Substance abuse treatment, prevention, and policy, 7 PMID: 22578101

Zhou K, Tang H, Sun Y, Huang GH, Rao LL, Liang ZY, & Li S (2012). Belief in luck or in skill: which locks people into gambling? Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming, 28 (3), 379-91 PMID: 21894576

Grötsch P, Lange C, Wiesbeck GA, & Lang U (2013). Pathological Gambling Induced by Dopamine Antagonists: A Case Report. Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming PMID: 24356928