chicot60
04-03-2011, 10:21 PM
By Richard Alleyne, Science Correspondent
A new set of genes linked to Alzheimer's has been discovered in a breakthrough that could pave the way to preventing 300,000 people developing the disease, claim scientists.
Five new genetic variants have been discovered, doubling the number already known, and meaning that together they account for 60 per cent of all cases of the disease.
The work, which has been hailed as "exciting", could lead to new treatments and preventions within the next 15 years, it was claimed.
Some of the genes are linked to inflammation and cholesterol in the brain which could mean that existing drugs could already exist to treat them.
Others suggest whole new mechanisms not previously linked to the disease.
"If we eradicate the affect of these 10 genes we could eradicate 60 per cent of Alzheimer's disease," said Professor Julie Williams at Cardiff University who led the international study.
Genetics is thought to account for between 60 and 79 per cent of the risk of developing Alzheimer's disease.
The rest is to do with lifestyle and environment.
The first gene connected to Alzheimer's was discovered 17 years ago, followed by four more two years ago.
This latest study, which is the biggest yet, added another five.
"What is most exciting is what these genes tell us," said Prof Williams.
"Five of the recently identified genes all have a role to play in the immune system.
"Four have functions at the cell surface and three are involved in moving fats around inside our cells.
"It’s likely that these processes have a key role to play in causing Alzheimer’s disease."
The results, published in the journal Nature Genetics, come from combining four separate genetic
studies into Alzheimer’s involving nearly 60,000 people worldwide.
It involved comparing the DNA of healthy people with the DNA of those with Alzheimer's disease.
The results were then compared with other studies in France and the USA to whittle down the number of genes.
The new common variants are listed as ABCA7, MS4A6A/ EPHA1, CD33 and CD2AP.
While earlier genes are connected to the build up of amyloid "plaques" which are thought to "silt up" the brain, the new variants have altogether different functions.
Several implicate the immune system, telling researchers there's something different about the immune system of people who go on to develop Alzheimer's disease.
Others implicate the processing of cholesterol and lipids in the brain as increasing the risk of developing the disease.
But "most exciting" is a new area of research which refers to a process called – endocytosis - a basic cell function which helps them process large molecules.
Together they offer "a very big clue" to what causes the disease, said the researchers.
Prof Williams said: "This study, plus our previous studies, means that we are beginning to piece together the pieces of the jigsaw and gain new understanding.
"We still have a long way to go – but the jigsaw is beginning to come together."
Rebecca Wood, Chief Executive of Alzheimer’s Research, which part-funded the study, said: "These findings are a step towards defeating dementia.
"We are yet to find ways of halting this devastating condition, but this work is likely to spark off new ideas, collaborations and more research."
There are currently 750,000 people in the UK have a form of dementia, more than half have Alzheimer’s disease.
In just 15 years a million people will be living with dementia.
This will soar to 1.7 million people by 2051, according to the Alzheimer’s Society.
It is estimated it already costs society £23billion a year.
http://www.telegraph.co.uk/health/healthnews/8422477/New-genes-found-in-hunt-for-Alzheimers-disease-cure.html
A new set of genes linked to Alzheimer's has been discovered in a breakthrough that could pave the way to preventing 300,000 people developing the disease, claim scientists.
Five new genetic variants have been discovered, doubling the number already known, and meaning that together they account for 60 per cent of all cases of the disease.
The work, which has been hailed as "exciting", could lead to new treatments and preventions within the next 15 years, it was claimed.
Some of the genes are linked to inflammation and cholesterol in the brain which could mean that existing drugs could already exist to treat them.
Others suggest whole new mechanisms not previously linked to the disease.
"If we eradicate the affect of these 10 genes we could eradicate 60 per cent of Alzheimer's disease," said Professor Julie Williams at Cardiff University who led the international study.
Genetics is thought to account for between 60 and 79 per cent of the risk of developing Alzheimer's disease.
The rest is to do with lifestyle and environment.
The first gene connected to Alzheimer's was discovered 17 years ago, followed by four more two years ago.
This latest study, which is the biggest yet, added another five.
"What is most exciting is what these genes tell us," said Prof Williams.
"Five of the recently identified genes all have a role to play in the immune system.
"Four have functions at the cell surface and three are involved in moving fats around inside our cells.
"It’s likely that these processes have a key role to play in causing Alzheimer’s disease."
The results, published in the journal Nature Genetics, come from combining four separate genetic
studies into Alzheimer’s involving nearly 60,000 people worldwide.
It involved comparing the DNA of healthy people with the DNA of those with Alzheimer's disease.
The results were then compared with other studies in France and the USA to whittle down the number of genes.
The new common variants are listed as ABCA7, MS4A6A/ EPHA1, CD33 and CD2AP.
While earlier genes are connected to the build up of amyloid "plaques" which are thought to "silt up" the brain, the new variants have altogether different functions.
Several implicate the immune system, telling researchers there's something different about the immune system of people who go on to develop Alzheimer's disease.
Others implicate the processing of cholesterol and lipids in the brain as increasing the risk of developing the disease.
But "most exciting" is a new area of research which refers to a process called – endocytosis - a basic cell function which helps them process large molecules.
Together they offer "a very big clue" to what causes the disease, said the researchers.
Prof Williams said: "This study, plus our previous studies, means that we are beginning to piece together the pieces of the jigsaw and gain new understanding.
"We still have a long way to go – but the jigsaw is beginning to come together."
Rebecca Wood, Chief Executive of Alzheimer’s Research, which part-funded the study, said: "These findings are a step towards defeating dementia.
"We are yet to find ways of halting this devastating condition, but this work is likely to spark off new ideas, collaborations and more research."
There are currently 750,000 people in the UK have a form of dementia, more than half have Alzheimer’s disease.
In just 15 years a million people will be living with dementia.
This will soar to 1.7 million people by 2051, according to the Alzheimer’s Society.
It is estimated it already costs society £23billion a year.
http://www.telegraph.co.uk/health/healthnews/8422477/New-genes-found-in-hunt-for-Alzheimers-disease-cure.html