Since the driver of the selection against the related gene seems to be malaria, I wonder if this is linked to prevalence of body hair on human ancestors.
Bug bites on hairless skin probably had something to do with dying of disease, and the early homonids that had the gene seem to be the ones hit the hardest.
We also see evolutionary markers related to bed bugs, head lice and body lice. Maybe mosquitos and genes linked to a possible malaria pandemic offer more clues.
Malaria is a fascinating one, with the prevalence of sickle cell anemia and G6PD blood deficiency in some populations with high exposure. Both of those cause health issues but they both confer some level of resistance to malaria.
As far as I remember, malaria comes in via glycosaminoglycans, and not our sialylated glycans. It could very well be related to our symbiosis with bacteria however.
Edit: I forgot the earlier work demonstrating Plasmodium specificity to NeuGc, so yeah maybe malaria!
Cats, being obligate carnivores and lacking a proper mechanism for extracting energy out of fatty acids (e.g. ketogenesis in humans), have actually very efficient kidneys to dispose of all the nitrogen coming from their protein-exclusive metabolism.
Domestic cats are at risk, but that is more a result of domestication and improper feeding (carbohydrate) than evolution or genetics. Unless I am missing something, of course! Care to elaborate?
They very much are, many pets will way overfeed themselves if given the opportunity.
Though it might also be human-inflicted, I don't know if wild animals will do so if provided with effortless unlimited amounts of food.
I would expect so though, most evolutionary environments simply don't set up organisms for an unlimited glut of free energy-dense food, when there's a glut of resources it's usually followed by some sort of crash, so organisms stock up as fast as they can in order to out-compete their peers once resources crash. If the glut doesn't end (which is essentially what modern advanced economies arrived at), neither does the tendency to stock up, because there's probably never been an evolutionary context (sustained for a long enough period) where that was an issue and thus allowed some organisms to outlive others.
Have you ever owned a cat or dog? My experience is that a percentage of them will overeat unless constantly monitored, eat things that are outright dangerous, etc. What is it that makes humans the stupid ones, here?
From the introduction: "There are many known risk factors, including blood cholesterol, physical inactivity, age, hypertension, obesity and smoking, but in roughly 15 percent of first-time cardiovascular disease events (CVD) due to atherosclerosis, none of these factors apply."
Or no other animal is smart enough to be able to produce an abundance of food for the scale of population that we can. And also no other animal has capitalism which motivates actors to make the food supply as addictive as possible.
The greatest risks to your health throughout history were (contagious) diseases and infections.
With the advent of sanitation, food safety, modern medicine, etc., their percentage
has dropped significantly.
But "you gotta die of something", so when one cause drops in rate, another rises. So if you're stubborn (lucky) enough not to die of anything else, it'll probably be either cancer or heart-related that gets you: up from 12% of all deaths in 1900 to 47% in 2010.[1]
In short, we're more likely to die of affluence diseases[2] if we're not dying of poverty diseases.[3]
Interesting, I was always under the impression that chipmunks were susceptible to heart attacks. I can't remember where I read it and I can't find a current source but you are apparently not supposed to harass chipmunks because they can experience stress induced heart attacks when threatened/chased. I've also seen potential evidence for this when my cat chased one around a parking lot only for it to collapse after sprinting around for a solid minute. It was immobile, looked short of breath and eventually died at some point between when I brought my cat in and the next morning.
> Interestingly, the evolutionary loss of the CMAH gene appears to have produced other significant changes in human physiology, including reduced human fertility and enhanced ability to run long distances.
Reduced fertility doesn't seem for me important, we have a contraception for that. But enhanced ability to run long distances seems very convenient. I can ride a bicycle or walk for hours just for fun of physical exercise, and I'm not going to lose that.
We could probably edit in a working copy, but I wouldn't be so quick to do that: Sialic acids are all over our cells, and we don't understand what the difference is between the two sialic acid types in terms of impact on molecular environment. One plus side to losing this gene is our ability to do long distance running.
Pets such as rabbits, hamsters, dogs are also prone to heart attacks. I think it has more to do with sedentary lifestyle. Unfortunately for most pets, it's not by choice.
This could also be "fixed" by dietary supplement, but you run the risk of aggravating your immune system. One way to introduce this back into the system is by consuming red meat. The conclusion from this is EMPHATICALLY NOT that to reduce the risk of CVD due to meat consumption you should eat more red meat. The immune effects likely are more damaging.
I've seen a mouse die in a "humane" trap after being carried a couple blocks – I always understood that was from a heart attack. It seems to happen with birds too – stress them out a bit, then dead.
So in what way are "only humans" prone? Are these not heart attacks?
“Overall, current research suggests that vitamin C deficiency is associated with a higher risk of mortality from CVD and that vitamin C may slightly improve endothelial function and lipid profiles in some groups, especially those with low plasma vitamin C levels. However, the current literature provides little support for the widespread use of vitamin C supplementation to reduce CVD risk or mortality.”
"Atherosclerosis is a disease in which plaque builds up inside your arteries....Plaque is made up of fat, cholesterol, calcium, and other substances found in the blood."
my TL;DR (as a non-doctor): LDL "cholesterol" (actually proteins carrying cholesterol and "fat" (triglycerides) in blood) has a tendency to get "stuck" in artery walls. That causes inflamation, which attracts macrophages which also get stuck, and so on until you get plaques ("clogged arteries") and one plaque breaks off and causes a heart attack. Consuming saturated fat / cholesterol is problematic because it causes a decrease of LDL-sensitive receptors and consequentially more LDL in blood. If I understand correctly, the later part of the previous statement is considered settled science ("we know how it actually works" - 1985 Nobel Prize was awarded for this), while the first part (diet) seems to be somewhat debated and has mostly statistical justification ("evidence suggests") and also depends on an individual's genetics.
So now we're including "survival of the unfittest" as part of evolutionary theory? Sorry, this makes zero sense. If humans really did evolve, then we hit the lottery - several times.
Fitness doesn’t mean what you think it means. As others have noted on this post, this mutation confers some resistance to malaria.
When the options are “malaria with high probability from birth onwards” or “heart attack after multiple decades with high probability if nothing else kills you first”, this is fitness.
Besides which, if humans didn’t evolve, you need to explain why the creator didn’t use a better mechanism to prevent us from getting malaria. For example: not creating malaria when they created us.
I like how the headlines explicitly states humans.
For yet another study in ... mice.
There are other options like dogs and pigs which are much better models for human biology, so if you really want to make a claim about subtle effects of human genetics you need to be as close to a human model as possible.
This is entirely ignoring the someone generous leap they make that one single gene mutation is responsible for an increased rate of heart disease. It also doesn’t touch on what the benefits for that gene were (to spread through the gene pool completely it must have some benefit that outweighs the cost)
Just for some background for those who weren't aware what is the OP all about. But to be fair, I think this article is actually well-written and doesn't contain sensationalized framing.
Further down in the study it says that removing the gene likely occurred because it made humans more resistant to malaria, and somehow it also enhanced the ability to run long distances.
crabLouse|6 years ago
Bug bites on hairless skin probably had something to do with dying of disease, and the early homonids that had the gene seem to be the ones hit the hardest.
We also see evolutionary markers related to bed bugs, head lice and body lice. Maybe mosquitos and genes linked to a possible malaria pandemic offer more clues.
fragmede|6 years ago
hirenj|6 years ago
Edit: I forgot the earlier work demonstrating Plasmodium specificity to NeuGc, so yeah maybe malaria!
bitwize|6 years ago
glastra|6 years ago
Domestic cats are at risk, but that is more a result of domestication and improper feeding (carbohydrate) than evolution or genetics. Unless I am missing something, of course! Care to elaborate?
raxxorrax|6 years ago
Maybe no other animal is just that stupid.
masklinn|6 years ago
They very much are, many pets will way overfeed themselves if given the opportunity.
Though it might also be human-inflicted, I don't know if wild animals will do so if provided with effortless unlimited amounts of food.
I would expect so though, most evolutionary environments simply don't set up organisms for an unlimited glut of free energy-dense food, when there's a glut of resources it's usually followed by some sort of crash, so organisms stock up as fast as they can in order to out-compete their peers once resources crash. If the glut doesn't end (which is essentially what modern advanced economies arrived at), neither does the tendency to stock up, because there's probably never been an evolutionary context (sustained for a long enough period) where that was an issue and thus allowed some organisms to outlive others.
klodolph|6 years ago
Have you ever owned a cat or dog? My experience is that a percentage of them will overeat unless constantly monitored, eat things that are outright dangerous, etc. What is it that makes humans the stupid ones, here?
Clor|6 years ago
raverbashing|6 years ago
And the title is a bit incorrect, other animals do suffer with heart issues/"heart attacks" (usually congenital, but due to old age as well)
cpp4life|6 years ago
dilawar|6 years ago
anvandare|6 years ago
But "you gotta die of something", so when one cause drops in rate, another rises. So if you're stubborn (lucky) enough not to die of anything else, it'll probably be either cancer or heart-related that gets you: up from 12% of all deaths in 1900 to 47% in 2010.[1]
In short, we're more likely to die of affluence diseases[2] if we're not dying of poverty diseases.[3]
[1] https://demography.cpc.unc.edu/2014/06/16/mortality-and-caus...
[2] https://en.wikipedia.org/wiki/Diseases_of_affluence
[3] https://en.wikipedia.org/wiki/Diseases_of_poverty
deanstag|6 years ago
edit: And also maybe general life style differences regarding availability and richness of food, exercise, shorter life spans etc.
cc439|6 years ago
unknown|6 years ago
[deleted]
ASalazarMX|6 years ago
But that would be from malnutrition, not atherosclerosis.
CamperBob2|6 years ago
The whole premise behind this headline seems bogus.
jedberg|6 years ago
ordu|6 years ago
> Interestingly, the evolutionary loss of the CMAH gene appears to have produced other significant changes in human physiology, including reduced human fertility and enhanced ability to run long distances.
Reduced fertility doesn't seem for me important, we have a contraception for that. But enhanced ability to run long distances seems very convenient. I can ride a bicycle or walk for hours just for fun of physical exercise, and I'm not going to lose that.
hirenj|6 years ago
zyang|6 years ago
hirenj|6 years ago
pvaldes|6 years ago
akvadrako|6 years ago
So in what way are "only humans" prone? Are these not heart attacks?
Rickvs|6 years ago
also-see|6 years ago
[deleted]
aszantu|6 years ago
[deleted]
watertom|6 years ago
[deleted]
JohnJamesRambo|6 years ago
https://www.quackwatch.org/01QuackeryRelatedTopics/pauling.h...
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5000725/
“Overall, current research suggests that vitamin C deficiency is associated with a higher risk of mortality from CVD and that vitamin C may slightly improve endothelial function and lipid profiles in some groups, especially those with low plasma vitamin C levels. However, the current literature provides little support for the widespread use of vitamin C supplementation to reduce CVD risk or mortality.”
ctack|6 years ago
[deleted]
glastra|6 years ago
What a way to start an article in a website with "science" in its name.
Atheroma is an accumulation of white blood cells. White. Blood. Cells. Not fat.
"Meat bad, saturated fat bad, eat your necessarily fortified grains and heart-healthy industrially extracted seed oils."
eevilspock|6 years ago
https://lmgtfy.com/?q=Atherosclerosis
"When plaque (fatty deposits) clogs your arteries, that’s called atherosclerosis."
~ American Heart Association (https://www.heart.org/en/health-topics/cholesterol/about-cho...)
"Atherosclerosis is a disease in which plaque builds up inside your arteries....Plaque is made up of fat, cholesterol, calcium, and other substances found in the blood."
~ https://www.nhlbi.nih.gov/health-topics/atherosclerosis
"Atherosclerosis refers to the buildup of fats, cholesterol and other substances in and on your artery walls (plaque), which can restrict blood flow."
~ https://www.mayoclinic.org/diseases-conditions/arteriosclero...
hirenj|6 years ago
-sclerosis is a hardening. E.g arthrosclerosis for a hardening of joints.
tomp|6 years ago
https://peterattiamd.com/the-straight-dope-on-cholesterol-pa...
my TL;DR (as a non-doctor): LDL "cholesterol" (actually proteins carrying cholesterol and "fat" (triglycerides) in blood) has a tendency to get "stuck" in artery walls. That causes inflamation, which attracts macrophages which also get stuck, and so on until you get plaques ("clogged arteries") and one plaque breaks off and causes a heart attack. Consuming saturated fat / cholesterol is problematic because it causes a decrease of LDL-sensitive receptors and consequentially more LDL in blood. If I understand correctly, the later part of the previous statement is considered settled science ("we know how it actually works" - 1985 Nobel Prize was awarded for this), while the first part (diet) seems to be somewhat debated and has mostly statistical justification ("evidence suggests") and also depends on an individual's genetics.
AnthonBerg|6 years ago
Pimpus|6 years ago
ben_w|6 years ago
When the options are “malaria with high probability from birth onwards” or “heart attack after multiple decades with high probability if nothing else kills you first”, this is fitness.
Besides which, if humans didn’t evolve, you need to explain why the creator didn’t use a better mechanism to prevent us from getting malaria. For example: not creating malaria when they created us.
mclightning|6 years ago
This is the second time I see skepticism about evolution is brought up on HN comments. Science literacy of the community definitely went down.
olliej|6 years ago
For yet another study in ... mice.
There are other options like dogs and pigs which are much better models for human biology, so if you really want to make a claim about subtle effects of human genetics you need to be as close to a human model as possible.
This is entirely ignoring the someone generous leap they make that one single gene mutation is responsible for an increased rate of heart disease. It also doesn’t touch on what the benefits for that gene were (to spread through the gene pool completely it must have some benefit that outweighs the cost)
segfaultbuserr|6 years ago
* Hyped-up science is a problem. One clever Twitter account is pushing back.
https://www.vox.com/future-perfect/2019/6/15/18679138/nutrit...
Just for some background for those who weren't aware what is the OP all about. But to be fair, I think this article is actually well-written and doesn't contain sensationalized framing.
rjzotti|6 years ago
pier25|6 years ago
unknown|6 years ago
[deleted]
AlexCoventry|6 years ago
fifnir|6 years ago
[deleted]