Alzheimer's Study Finds 42 More Genes Linked To Higher Risk of Disease (theguardian.com) 28
An anonymous reader quotes a report from the Guardian: The largest genetic study of Alzheimer's to date has provided compelling evidence linking the disease to disruption in the brain's immune system. The study, using the genomes of 100,000 people with Alzheimer's and 600,000 healthy people, identified 75 genes linked to an increased risk of the disease, including 42 that had not previously been implicated. The findings suggest degeneration in the brains of dementia patients could be spurred on by "over-aggressive" activity in the brain's immune cells, called microglia.
The study, the largest of its kind to date, also allowed scientists to devise a genetic risk score that could predict which patients with cognitive impairment would, within three years of first showing symptoms, go on to develop Alzheimer's. The score is not intended for clinical use at the moment, but could be used when recruiting people for clinical trials of drugs aimed at treating the disease in the earliest stages. The latest work highlights different sets of genes seen in more common forms of Alzheimer's, including a role for the immune system. "If [at the outset] we'd seen the genetics of common disease, we would've said this is an immune disease," said professor Julie Williams, the director of the UK Dementia Research Institute at Cardiff University and a co-author of the study. "It's not the same disease."
Risk genes highlighted in the study include ones that affect how efficiently the brain's immune cells, microglia, clear away tissue that is distressed. In people at risk, these housekeeper cells appeared to be working too aggressively. A similar pattern was found for genes that control how readily synapses, which connect neurons, send out an "eat me" signal when in distress. The high-risk variants appeared to lower the threshold for synapses sending out distress signals, causing the brain to purge connections at a quicker rate. The findings, published in the journal Nature Genetics, fit with previous results pointing to a role for the immune system. People with diabetes, which affects the immune system, are at considerably higher risk, for instance, and once dementia has been diagnosed infections can trigger more rapid cognitive decline.
The study, the largest of its kind to date, also allowed scientists to devise a genetic risk score that could predict which patients with cognitive impairment would, within three years of first showing symptoms, go on to develop Alzheimer's. The score is not intended for clinical use at the moment, but could be used when recruiting people for clinical trials of drugs aimed at treating the disease in the earliest stages. The latest work highlights different sets of genes seen in more common forms of Alzheimer's, including a role for the immune system. "If [at the outset] we'd seen the genetics of common disease, we would've said this is an immune disease," said professor Julie Williams, the director of the UK Dementia Research Institute at Cardiff University and a co-author of the study. "It's not the same disease."
Risk genes highlighted in the study include ones that affect how efficiently the brain's immune cells, microglia, clear away tissue that is distressed. In people at risk, these housekeeper cells appeared to be working too aggressively. A similar pattern was found for genes that control how readily synapses, which connect neurons, send out an "eat me" signal when in distress. The high-risk variants appeared to lower the threshold for synapses sending out distress signals, causing the brain to purge connections at a quicker rate. The findings, published in the journal Nature Genetics, fit with previous results pointing to a role for the immune system. People with diabetes, which affects the immune system, are at considerably higher risk, for instance, and once dementia has been diagnosed infections can trigger more rapid cognitive decline.
A part of the whole. (Score:2)
I have observed that dementia runs in families so this explains part of it. Environmental factors may be the rest.
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Alzheimer's has a genetic component but is also correlated with lack of exercise, insufficient sleep, smoking, and lousy diets.
For people of the same age, blacks are the most likely to suffer from dementia, and Asians the least. That makes sense since it correlates with life expectancy. Asians live longer, so there is more evolutionary pressure to weed out genes associated with dementia.
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Alzheimer's has a genetic component but is also correlated with lack of exercise, insufficient sleep, smoking, and lousy diets.
oh no i'm fucked
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Alzheimer's has a genetic component but is also correlated with lack of exercise, insufficient sleep, smoking, and lousy diets.
oh no i'm fucked
You aren't missing anything. The bad part about living longer is that it's all on the wrong end of life.
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Asians live longer due to lifestyle choices. People of African descent can live just as long, for example, Violet Brown of Jamaica who died a few years ago lived to age 117. Only 6 people, Asian or not are known to have lived longer. The second-longest living American in history, Susannah Mushatt Jones, is of African descent.
My guess is if you control for diet and other factors most races would be almost equivalent. There isn't as much diversity in human genetics as people think.
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My guess is if you control for diet and other factors most races would be almost equivalent. There isn't as much diversity in human genetics as people think.
Humans are a product of evolution, of the environment our ancestors lived in. My ancestors had a huge drop in health and stature several thousand years ago when they switched from hunter-gathering to agriculture, with a more reliable but less-varied and high-carb diet. It took thousands of years for evolution to adapt us to that new diet and environment sufficiently to be as healthy as our stone-age ancestors (when they didn't starve or get eaten).
But some races such as the aborigi
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Part the First: The genetic variation outside of Africa is indeed very, very slight. But you only need one SNP to make a huge difference, so we can't trust that the variation is unimportant merely because it's small.
Part the Second: Ikaria is going to be inhabited by people who are genetically not much different from other Greeks, and indeed that is the opinion of some researchers, but it has a significantly greater number of people living to over 100 than the rest of Greece and other Greek islands. Now, it
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My guess is if you control for diet and other factors most races would be almost equivalent. There isn't as much diversity in human genetics as people think.
Humans are a product of evolution, of the environment our ancestors lived in. My ancestors had a huge drop in health and stature several thousand years ago when they switched from hunter-gathering to agriculture, with a more reliable but less-varied and high-carb diet. It took thousands of years for evolution to adapt us to that new diet and environment sufficiently to be as healthy as our stone-age ancestors (when they didn't starve or get eaten). But some races such as the aboriginal Australians have only had a few generations since then, and with cheap tasty junk food available, they have terrible rates of diabetes and other chronic illnesses. All humans have this problem, but some races much worse than others, for reasons of biology and evolutionary history. You can't simply "control for diet".
Samoan people also have that issue. they've microevolved to thrive on a high protein diet as people on an island would, and now the western diet is wrecking their physiology.
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The genetic diversity outside of Africa is extremely small. Most of the diversity is inside of Africa. This makes long African and Asian lifespans interesting because Asia is included in the people with very little genetic diversity and Africans.
Now, there ARE genes implicated in longevity, and there's the matter of telomere length, but yes you're absolutely right that lifestyle choice is the bulk of it.
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You anecdotal evidence means nothing. I don't doubt Asians might live longer due to diet. That is a statistic though (assuming it is true). Claiming some Jamaican dear lived until 117 means nothing other than she lived until 117.
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Asians live longer due to lifestyle choices. People of African descent can live just as long, for example, Violet Brown of Jamaica who died a few years ago lived to age 117. Only 6 people, Asian or not are known to have lived longer. The second-longest living American in history, Susannah Mushatt Jones, is of African descent. My guess is if you control for diet and other factors most races would be almost equivalent. There isn't as much diversity in human genetics as people think.
Not a disagreement, just a point to chime in. What would be your guess as to how much better the longest lived are having superior life outcomes?
I recently saw a video of a super old Monk, I think also 117 years old. Nightmare fuel. Seriously skeletal, I mean it looked like CG of an animated skeleton, bedridden, and now pointlessly living.
I'll take quality of life over length. If that beer with friends takes a few months off my life at the deteriorated end, I'll gladly accept the good time I'me having
Re:A part of the whole. (Score:4, Informative)
As the article notes, the signs all show that Alzheimers' appears to be a CNS immune response gone wrong (the CNS has its own semi-independent immune system). So various external factors may affect your risk of getting trigger pathogens in the CNS or how heavily your immune system responds to them, but ultimately, it's the pathogen and the response to it that appears to be the root cause. Two main culprits suggested are P. gingivalis (the bacteria that causes gingivitis) and esp. herpes simplex (both 1 (cold sores) and 2 (genital)).
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As the article notes, the signs all show that Alzheimers' appears to be a CNS immune response gone wrong (the CNS has its own semi-independent immune system). So various external factors may affect your risk of getting trigger pathogens in the CNS or how heavily your immune system responds to them, but ultimately, it's the pathogen and the response to it that appears to be the root cause. Two main culprits suggested are P. gingivalis (the bacteria that causes gingivitis) and esp. herpes simplex (both 1 (cold sores) and 2 (genital)).
I agree with you 100 percent. The problem with this version is that it will offend the people who believe that we all need to be personally blamed for all our physical problems.
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So far off that I'm surprised it wasn't modded Insightful, though as usual I was looking for Funny and as usual I was disappointed.
Reproduction is before Alzheimers, so no selection there.
Only if the population reproduces later in life (Score:2)
Genes are not passed on beyond reproductive age. So your theory could only be correct if a specified group not only lived longer, but also reproduced later in their lives.
Remember, Facebook is the creator of the “Slap a Teacher TikTok challenge," not TikTok:
https://www.washingtonpost.com... [washingtonpost.com]
Re: A part of the whole. (Score:1)
It's really 24 (Score:1)
Doc just remembered it wrong.
I think these geneticists are., (Score:1)
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You really don't grasp how this works, do you?
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According to you, every scientist announcing findings is fishing for grants. One wonders how science progresses in your demented little world.
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It's worse. A genetic link can mean one that increases a risk by one in a hundred million, and which is only active if X, Y and Z happen. Where the scientists state the triggers and contribution clearly.
This, according to Fud, is fearmongering.
A simple solution (Score:2)
Objoke1 (Score:2)
My wife said to me "If I ever get Alzheimer's I would commit suicide rather than burdening you with me"
I said "That's the fifth time you've said that today"
Objoke 2 (Score:2)
My 90 year old neighbor has Alzheimer's.
And every morning when i wake up he's in a panic knocking at my door asking if I'd seen his wife, and every day i am forced to remind him that she has been dead for over 10 years...
Honestly i could just move, the house isn't too great, and I've had many opportunities to live in better places..
But the look of pure joy on his face every time i tell him she's dead just makes my day and keeps me from leaving.
Objoke 3 (Score:2)
Lots of cops seem to suffer from Alzheimer's.
Every time I get pulled over by a cop, they ask me:
“Do you know why I pulled you over?”