Evolutionary Gene Loss May Help Explain Why Only Humans Are Prone To Heart Attack (sciencedaily.com) 145
An anonymous reader quotes a report from ScienceDaily: A decade ago, Nissi Varki, MD, professor of pathology at UC San Diego School of Medicine, with co-author Ajit Varki, MD, Distinguished Professor Of Medicine and Cellular And Molecular Medicine, and colleagues noted that naturally occurring coronary heart attacks due to atherosclerosis are virtually non-existent in other mammals, including closely related chimpanzees in captivity which share human-like risk factors, such as high blood lipids, hypertension and physical inactivity. Instead, chimp "heart attacks" were due to an as-yet unexplained scarring of the heart muscle. In the new study, the Varkis, and Philip Gordts, PhD, assistant professor of medicine, and others report that mice modified to be deficient (like humans) in a sialic acid sugar molecule called Neu5Gc showed a significant increase in atherogenesis compared to control mice, who retain the CMAH gene that produces Neu5Gc.
The researchers -- members of the Glycobiology Research and Training Center and/or the Center for Academic Research and Training in Anthropogeny at UC San Diego -- believe a mutation that inactivated the CMAH gene occurred a few million years ago in hominin ancestors, an event possibly linked to a malarial parasite that recognized Neu5Gc. In their findings, the research team said human-like elimination of CMAH and Neu5Gc in mice caused an almost 2-fold increase in severity of atherosclerosis compared to unmodified mice. The researchers note that humans are repeatedly exposed to Neu5Gc when they consume red meat, as it prompts an immune response and chronic inflammation they call "xenosialitis." "In their tests, human-like mice modified to lack the CMAH gene were fed a Neu5Gc-rich, high-fat diet and subsequently suffered a further 2.4-fold increase in atherosclerosis, which could not be explained by changes in blood fats or sugars," reports ScienceDaily.
The study has been published in the journal PNAS.
The researchers -- members of the Glycobiology Research and Training Center and/or the Center for Academic Research and Training in Anthropogeny at UC San Diego -- believe a mutation that inactivated the CMAH gene occurred a few million years ago in hominin ancestors, an event possibly linked to a malarial parasite that recognized Neu5Gc. In their findings, the research team said human-like elimination of CMAH and Neu5Gc in mice caused an almost 2-fold increase in severity of atherosclerosis compared to unmodified mice. The researchers note that humans are repeatedly exposed to Neu5Gc when they consume red meat, as it prompts an immune response and chronic inflammation they call "xenosialitis." "In their tests, human-like mice modified to lack the CMAH gene were fed a Neu5Gc-rich, high-fat diet and subsequently suffered a further 2.4-fold increase in atherosclerosis, which could not be explained by changes in blood fats or sugars," reports ScienceDaily.
The study has been published in the journal PNAS.
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Many Health stories have "MAY" in the title. (Score:2)
Many of the titles of stories about health have the word "MAY" in the title. A lot of what is called health news is unfinished, sloppy, or illogical thinking.
(I didn't link to Google Health News because each link has encrypted coding, hiding what is being communicated.)
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We know what "may" means... with high certainty
So, we may know what "may" means.
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You seem to think that certitude is evidence of credibility. In the world of science reporting, (and in most domains, if we're being honest) exactly the opposite is true. Especially when it comes to medicine, health, and nutrition, anybody who doesn't cover their claims with abundant qualifiers is most likely peddling completely unproven snake oil.
Consider the details, not just the title. (Score:2)
One story of MAJOR sloppiness: In a review of 337,000 patient cases, this was the No. 1 most common preventable medical error. [marketwatch.com] Quote:
"Under-trained and burned-out providers along with understaffed services are also key contributors to preventable patient harm, making training and funding for the workforce vital..."
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The important detail for your example is that the scientists aren't the ones treating patients. Do you also look at politicians to learn about plumbers?
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Re:Pigs? (Score:5, Informative)
Chickens and geese aren't mammals.
atherosclerosis are virtually non-existent in other mammals
Heart attacks in chickens is primarily from microscopic lesions, where as atherosclerosis (as commonly seen in humans) is a build of up plaques on the artery wall.
Dogs with reduced thyroid function can get atherosclerosis too, so the article (which I did not read) is misleading. Other factors leading to atherosclerosis in dogs are Cushing's disease and diabetes (DM).
Re: Pigs? (Score:2, Insightful)
It might occur to someone that other mammals have shorter life spans. A dog that lives 7 to 10 years wouldn't be likely to build up fatty plaques in heart arteries, the same with most other mammals like pigs and mice
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Humpback whales live hundreds of years, not bad for a mammal. African elephants live lifespans comparable to humans. If you look at birds, there's a macaw that was born 1899 and still crotchety.
It's only humans that have this problem. And when we artificially recreate the problem in short lived mice, they die even younger. Has nothing to do with the normal lifespan.
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I didn't read the article either, but dogs also don't have CMAH, so it's at worst only misleading in a "not detailed enough" sense.
Rob
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I wouldn't be surprised (Score:1)
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There are many different modes of heart failure. This particular mode is unique to humans.
Or don't eat meat? (Score:2, Interesting)
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Fewer for some chronic diseases, increases in others. It's not particularly rare that vegan women will stop their periods in their 20s and they'll restart when they add back animal products to their diets.
Just look at our anatomy if you want to see what we are. We have incisors to rip meat but molars to crush plants. Our digestive tracts are far longer than a carnivore yet far shorter than an herbivore. Quite simply, we are omnivores. We can eat animal products, as they're easier to digest, we can eat
India has heart disease due to genetics, moron. (Score:2, Interesting)
Saying India is "largely" vegetarian is a completely bullshit non-fact, and you're pretending animal products aren't widely used in their diets. Both are false characterizations.
Re:Or don't eat meat? (Score:5, Informative)
Re:Or don't eat meat? (Score:5, Interesting)
Are you denying the existence of healthy vegetarians? there are plenty of ways to get protein from plant based sources (chickpeas, beans, lentils, tofu, etc).
No one has to eat meat. It is not *required* to live as you seem to be implying.
Infact, going forward a hundred years, there will most likely not be any sort of meat farming period. Its simply too expensive and unsustainable.There will be lab meat and probably expensive artisan beef, but no more factory farms.
There is a great documentary about how much damage a meat based diet does to people. its called forks over knives [imdb.com]
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Are you denying the existence of healthy vegetarians?
Not if they are eating fish and eggs, but the vegans are indeed all in various pathological states. There is no problem sustaining civilization for 100 years or more if the population does not explode due to migration from starving areas without factory farms
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" Our digestive track"
Yeah, I'll take my diet advice from someone who can't spell tract.
Sure.
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Some soil supports only grass (Score:2)
Actually vegetables and grains are in fact food for as long as human evolution has been a thing
Provided a particular piece of land is suitable for growing "vegetables and grains." Some soil supports only grass, and pasture for ruminants is an arguably more efficient use of that land.
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Wheat is just a grass with big seeds. But we grow both corn and wheat on flat land so that we can utilize machine cultivation. On hills, we let grass grow for cattle, as they don't mind a slope. We do need to solve the problem of methane-rich cow burps, though.
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Re:Or don't eat meat? (Score:5, Informative)
"The title of the article insists we are meat eaters. Are we? Our digestive track looks a lot like chimps, so they're comparing apples and oranges, "
http://www.bbc.com/earth/story... [bbc.com]
Chimpanzees eat meat. If you get near a point, make it.
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https://janegoodall.ca/our-stories/10-things-chimpanzees-eat/
"However, meat and other animal products can account for 6% of a chimpanzee’s diet. "
Eating 6% meat would be distinctly different to current human diets, especially the American one.
Re:Or don't eat meat? (Score:5, Funny)
Eating 6% meat would be distinctly different to current human diets, especially the American one.
They probably used to eat more, but they're running out of monkeys.
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Our digestive tracts look nothing like an herbivore's digestive tract. Instead, it resembles other omnivore's digestive tracts. Implying we evolved as omnivores.
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Our digestive track looks a lot like chimps
Our small intestine is longer. The chimp's colon is bigger.
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Well, we are omnivores.
There is a good bit of study that also shows that when man evolved into a meat eater, that enabled his brain to grow larger and therefore eventually migrate himself to the top of the food chain, as the human being we know today.
So, meat eating IS a good thing, but like all good things, in moderation is best.
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Wouldn't that be devolution? (Score:1)
Re:Wouldn't that be devolution? (Score:5, Interesting)
There's a hypothesis that the loss of the Neu5Gc gene helped human ancestors to survive a malaria epidemic.
Re:Wouldn't that be devolution? (Score:5, Insightful)
Loss of genetic information is an adaptation to the environment. Think of it as tossing out what you don't need to lighten the load, remembering that as far as evolution is concerned, "need" is the ability to pass the genome to the next generation; nothing else counts.
Evolution isn't some progress to a higher ideal; it's the survival of the genome, nothing more, nothing less. "Devolution" is a null word; it has no meaning. It's all evolution.
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Every gene in the genome must be copied at cell division. The energy cost for this is small, but it exists. The energy cost is greater if the gene is expressed, since whatever it codes for is being synthesized, with much greater costs. Thus an unneeded, unexpressed gene has slight selection pressure for its elimination, small enough that it can continue to exist for millenia. A gene that is expressed, but creates something for which there is no need has a much higher selection pressure for its eliminati
Re:Wouldn't that be devolution? (Score:4, Informative)
You can't call everything, including loss of genetic information, 'evolution'.
Evolution already includes all of that, it's not an abuse of terminology.
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I don't think so. "Evolution" as an all-encompassing "cause" is a trivially easy argument, if you just call whatever happens "evolution" and it's demonstrated correct as "evolution" because something happened.
That's both circular and unfalsifiable.
There are several views positing that the core process is a loss of genetic information from one or more genetic "seeds", e.g. the Panspermia hypothesis. Lumping them all under "evolution" is equivalent to terminating significant lines of investigation a priori
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1) The macroevolution versus microevolution question was started by scientists, not theists. And at base it is a question of probability derived from the complexity of the biological system under consideration, while maintaining survivability through the intermediate non-functional stages, and this question remains fully valid.
2) Contrary to your disingenuous false dichotomy, I am not a "creationist" as you deliberately misapply it, I, like Origen as a -second century- Christian, do not believe in literal
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You ran to your blind alley of nihilism remarkably quickly.
I know because of what I've experienced while living, and dying won't change that.
But to leave you with something for now, I'll suggest a simple starting point for your metaphysical consideration:
"If the universe were to vanish, would the rules of chess remain the same?"
I'll collect the rest of your pieces later.
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You can't call everything, including loss of genetic information, 'evolution'.
Kimuran Neutral Evolution [wikipedia.org]. BTW, the wikipedia article is only a brief introduction that doesn't give a good impression of just how much impact it has.
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Losers (Score:5, Funny)
Only losers get heart attacks anyw
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But we won't get them in space, so clearly the species needs to leave this planet.
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Considering I have had 2 heart attacks, second one even after I did everything my Doc told me to do. Who am I to call someone a loser.
Peace
Mice are not humans. Not even close. (Score:3, Interesting)
Heart attacks are a mystery. If you look at https://drmalcolmkendrick.org/... [drmalcolmkendrick.org] you will see the latest (63rd) part of Dr Malcolm Kendrick's cogitations about the causes of heart disease, stroke, etc. Dr Kendrick is a very well-informed and thorough doctor who has made it his business to investigate the topic - and so far he has come to no definite conclusion. (Hint: it isn't "cholesterol" in any shape or form, although stress is in the mix). http://www.zoeharcombe.com/201... [zoeharcombe.com]
One thing is quite sure: while studies on mice may give us interesting leads to follow up, you really can't compare a mouse's diet, metabolism and biochemistry with a human's. Not when you are after something as complex and elusive as the cause of heart attacks.
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Dr Kendrick is a quack and a bullshit artist who chooses to ignore all of the heart disease studys back to the Framingham study.
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Dr Kendrick is a quack and a bullshit artist who chooses to ignore all of the heart disease studys back to the Framingham study.
That turns out not to be the case.
Might be ... (Score:2)
..because pigs and chimpanzees rarely complain about chest pain.
I'm suffering reading comprehension issues. (Score:1)
The first two paragraphs seem to state that some change in humans caused a reduction in some stuff that prevents heart attacks. Then, the last sentence states that the stuff causes heart attacks. Reading the linked article confirms this.
As best I can tell, this study concludes nothing.
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We've known for a long time that heart disease runs in families, and we now can say that certain genes are associated with it. The best solution is pick better parents, but since we don't have time machines, we get the heart we're dealt.
But just as there was some random mutation that allowed heart disease into the gene pool, there are other mutations that have entered the gene pool that can reduce risk. Some people have a mutation that results in very low levels of LDL and very high levels of HDL cholest
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This study concluded disabling one gene (that is disabled in humans) made mice experience a problem that's unique to humans.
The paragraph at the end says when this "foreign" chemical gets into a human, the human's immune system goes after it. Which may explain some things. But the paragraph is clearly not talking about this study, it's ScienceDaily talking about other research into the same molecule.
Could it possibly be... (Score:1)
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You haven't seen our local gaze of raccoons dining in the fast food restaurant dumpsters.
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Yes, but how are their blood lipids doing?
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Don't know. That's protected information under HIPAA.
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Wild mammals prefer Panera.
I don't get it: Neu5Gc vs CMAH gene (Score:2)
Seems to say that deficiency of Neu5Gc is a bad thing. So a Neu5Gc-rich diet is good. But wait
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"human-like mice"? (Score:1)
"human-like mice".
Boy, I'd like to see what one of those look like. My mind is racing!
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Jerry on "Tom and Jerry"?
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. guilt . (Score:1, Offtopic)
As every American knows, bad things happen to us because we are guilty.
Since the time of Martin Luther, Christians have had to take responsibility for our sins, our ignorance, our complacency. We must pull ourselves up by our bootstraps and forge ahead. That's what the New World meant for Protestants of all stripes.
Today it's been drummed into our heads that smoking, drinking and sex are the cause of many a misfortune. Wrong lifestyle, wrong diet, wrong exercise routine- it's all our fault. From the homeles
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Because, yes, objectively, smoking, drinking, and sex are the cause of many a misfortune. I don't say this because I'm a Christian (who has done all three, and paid a price for it), but because it's simple fact. And, I avoid the blatant irrationality of an argument that the correct view of anything is -automatically- the opposite of whatever a particular (and yes, the fact you have a -particular- one
Confused (Score:2)
"modified to be deficient (like humans) in a sialic acid sugar molecule called Neu5Gc showed a significant increase in atherogenesis compared to control mice, who retain the CMAH gene that produces Neu5Gc. "
So this says that if you don't have enough Neu5Gc you will get more heart attacks.
"The researchers note that humans are repeatedly exposed to Neu5Gc when they consume red meat, as it prompts an immune response and chronic inflammation they call "xenosialitis." "In their tests, human-like mice modified to
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Re: Evolution "theory" is a hoax (Score:5, Funny)
And donâ(TM)t even get me started on the so called "theory" of gravity.
ELI5: How'd this gene get lost? (Score:5, Interesting)
Explaining like you're five, in case you're reading with your children:
1. When your body copies half of its genome into your unborn child's body, it makes mistakes called mutations. Mistakes that hurt offspring's chance of survival in a particular situation won't allow the children to survive to copy their genomes, while mistakes that help them will let them make more grandchildren for you. Over hundreds of generations, enough mistakes are made that two populations are different enough not to be able to make children anymore.
ObTopic: For example, before the invention of farming, people didn't have much of an opportunity to eat enough to cause heart disease. Thus at that time, mistakes affecting certain genes that protect the heart did not hurt people.
2. "Theory" means humanity's best explanation to predict the effect of a particular natural phenomenon. Gravity as a stretching of space itself explains both how an apple falls toward the earth and hits it and how the moon falls toward the earth and misses.
3. Some electromagnetic waves are visible, such as the light waves coming out of your computer's monitor. It's just that human eyes can receive only a narrow band of frequencies. Some lower frequencies can go through walls and are useful for sending words and music to devices used by other people.
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I'd like to invite you to my church this Sunday.
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Now down to business. Would you like to subscribe to my newsletter?
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Well, allow me to explain it unironically.
We have a way of dealing with the natural world we call "science". In science we use certain methods that, over the course of more than 4000 years have allowed us to understand and manipulate the natural world to such an extent we are now at risk of destroying large parts of it.
This is an undeniable success of the methods in use. When we apply those methods to domains such as biology we have similar successes. We have found DNA (tiny things in your body that contain
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No, that is not the problem. The problem is a genetic deficiency causing all that stuff to be a problem, where it isn't in chimps and mice -- until they are forced to duplicate our issue.
Your statement is an evolved meme retread of gluttony-is-evil, as wrung through modern politics.
Gluttony was evil becaise of starvation. Now capitalism has conquered that, so the meme must evolve or it stops spreading between meme instantiation units, AKA people. So it is evil for biological effects.
But those effects are