home
RSS
July 11th, 2012
06:27 PM ET

Rare genetic mutation protects against Alzheimer's

With more than 5 million Americans suffering from Alzheimer's disease, the most common form of dementia, the race is on to surface clues about causes and prevention.

An important breakthrough for the research field comes in the journal Nature this week. Researchers say they found a rare genetic mutation in Iceland that appears to protect against Alzheimer's disease.

The mutation appears to slow the production of the beta-amyloid protein, long considered to be a cause of Alzheimer's. This mechanism helps validate the theory that beta-amyloid plaques - an accumulation of the protein - cause this form of dementia for which no cure has been found. The research team was led by Dr. Kari Stefansson, chief executive of the Icelandic company DeCode Genetics. They studied data from the genomes of nearly 1,800 Icelandic people.

A genetic test for the protective mutation wouldn't make sense, since it's so rare, experts said. If you really wanted to know if you have it, your doctor probably couldn't tell you; it would require a specialized research lab, says Dr. Sam Gandy, director of the Mount Sinai Center for Cognitive Health.

Mutations like this are "not so good for screening as they are for teaching what’s going on," said Rudolph Tanzi, a Harvard Medical School neurologist who was not involved in this study.

Drugs attempting to clear some of those plaques out have so far failed to reverse the effects of dementia in clinical trials, but this new study drives home that targeting beta-amyloid is still correct, Tanzi said.

There are going to be more failures before a successful treatment is found, Tanzi said.  Drugs that have failed so far weren't getting into the brain, had harmful side effects or were just defective.  A new wave of clinical trial results will come this fall - if they too fall short, this study reinforces that researchers should still go after beta-amyloid, Tanzi said.

It might be another four or five years before drugs under development start showing more promising results, he said. "These are just not yet the right drugs, and I think the right ones are yet to come," he said.

A successful protective drug against Alzheimer's would probably have to be taken for decades, like a statin to reduce risk of heart problems, said Dr. Robert Green, associate director of medicine in the division of genetics at Brigham and Women’s Hospital and Harvard Medical School. It could be something everyone takes, and perhaps the people most at risk of Alzheimer's would start on it earlier.

This study suggests that when someone has this specific mutation, the amount of beta-amyloid protein released into his or her brain, which contributes to Alzheimer's, might be reduced by as much as 40%. This could explain lower rates of dementia.

For most of us, who do not have this mutation, beta-amyloid protein gets released when the amyloid precursor protein (APP) on a brain cell is cut by two enzymes: Beta-secretase and gamma-secretase. (A third enzyme that snips it, alpha-secretase, actually prevents Alzheimer's-related plaques from forming).

Drug developers have tried inhibiting gamma-secretase, but because that enzyme is responsible for so many other important things, these drugs were toxic. "You can't just hit it with a sledgehammer," Tanzi explains. The same goes for beta-secretase.

"You need an enzyme that will block beta-secretase or gamma-secretase from clipping just APP, but you need to allow it to do its other jobs," Tanzi said. He and colleagues received a grant from the National Institute of Health to develop drugs along these lines.

The Nature study suggests when people have the newly discovered mutation on the APP gene, they naturally experience less cutting from beta-secretase, resulting in lower amounts of beta-amyloid getting into the brain from birth. This seems to be a protection against Alzheimer's.

In 1987, Tanzi led a group that discovered the APP gene, on which the protective mutation was found. This gene is associated with early-onset Alzheimer's disease. In 2009, his research team found two different rare mutations on this gene that raise the risk of Alzheimer's.

Early symptoms of Alzheimer's include difficulty remembering names and recent events, apathy and depression.  As the disease progresses, patients often exhibit disorientation, confusion and severe impairments in walking, speaking and swallowing.

Lifestyle changes such as increased physical activity, lowered stress and healthy diet have found to be associated with staving off dementia, but there has been no definitive proof or treatment developed.

Related: Spinal tap may predict Alzheimer's years ahead


soundoff (141 Responses)
  1. Free Vbucks Generator

    https://actcycle.jp/construction/r360.html

    https://www.fortnitecode.net/

    January 26, 2021 at 12:57 | Report abuse | Reply
  2. Free Vbucks

    https://www.blackandblue.nl/tiffosi-one-size-fits-all-testvideo/

    https://www.vbuckscode.net/

    January 27, 2021 at 18:22 | Report abuse | Reply
  3. Free Vbucks

    http://triron.ch/3column/

    https://www.fortnitecodes.org/

    January 27, 2021 at 18:34 | Report abuse | Reply
  4. Free V bucks

    http://www.iratxoelkartea.com/eu/campeonato-de-botxas-de-iratxo/

    https://www.fortnitecode.net/

    January 27, 2021 at 18:45 | Report abuse | Reply
  5. Free Vbucks

    https://hyundai-kontum.com/bao-duong-dinh-ky/

    https://www.free-v-buck.net/

    January 27, 2021 at 18:55 | Report abuse | Reply
  6. Free V bucks

    https://www.bayareakg.com/july-2019-meeting/

    https://www.fortniteredeemcode.net/

    January 27, 2021 at 19:26 | Report abuse | Reply
  7. Free Vbucks Generator

    https://wildtroutstreams.com/great-basin-id/

    https://www.fortnitecodes.org/

    January 28, 2021 at 15:07 | Report abuse | Reply
  8. Free Vbucks

    http://descubrirmarruecos.com/deja-aqui-tu-comentario/

    https://www.fortniteredeemcode.net/

    January 28, 2021 at 15:15 | Report abuse | Reply
  9. Free V bucks

    https://www.magherabuoy.co.uk/home/attraction1/

    https://www.fortniteredeemcode.net/

    January 30, 2021 at 06:46 | Report abuse | Reply
  10. Free Vbucks Generator

    https://kmfkombucha.com/line_distance_bleuet-2/

    https://www.howtogetfreevbucks.org/

    January 30, 2021 at 06:55 | Report abuse | Reply
  11. Game Trick

    What is it called to be a computer tech that works on business computers?

    https://www.illustratedfaith.com/members/regulusgame/activity/738340/

    February 4, 2021 at 05:35 | Report abuse | Reply
  12. Game Tips

    How can I make a personalized banner for a blogspot blog?

    http://foto-samoletov.ru/user/regulusgame/

    February 4, 2021 at 10:19 | Report abuse | Reply
  13. Roblox Tips

    What joomla component would you recommend for member photo uploads?

    https://articlescad.com/helping-you-know-how-video-game-cheat-rules-operate-533051.html

    February 4, 2021 at 17:11 | Report abuse | Reply
  14. Game Info

    I wanted to start my own blog and I was looking for your suggestions for which sites you think are the best to start one with. . I want to be able to post pictures, text, and music (maybe).. I only want to use a free blog host..

    http://nqbtv.com/home.php?mod=space&uid=2552596

    February 4, 2021 at 17:14 | Report abuse | Reply
  15. Regulus Game

    I was thinking of publishing or posting online some of my articles I've written for school but can't afford to copyright them. If they are in my school paper, do I hold any ownership over them or are they protected by law?.

    https://www.instapaper.com/p/regulusgame

    February 4, 2021 at 17:17 | Report abuse | Reply
  16. Roblox Tips

    Am i legally responsible for content on my blogs & forums that others have written?

    http://zoe-beauty.be/user/regulusgame/

    February 4, 2021 at 17:20 | Report abuse | Reply
  17. Regulus Game

    i need some ideas for a blog. i already do poems and surveys on it but i wanna talk about something..

    http://bbs.01bim.com/home.php?mod=space&uid=242633

    February 4, 2021 at 17:27 | Report abuse | Reply
  18. Game Info

    How do I add the shadows to a Joomla template?

    https://hamronepalibazar.com/user/profile/172133

    February 4, 2021 at 22:02 | Report abuse | Reply
  19. Coin Master Tips

    How do I start my own website about fantasy sports?

    https://topsitenet.com/article/868131-obtain-the-xbox-game-tricks-and-tips-you-have-to-get-ahead-of-time/

    February 4, 2021 at 22:04 | Report abuse | Reply
  20. Roblox Tips

    I follow all the installation instructions, after downloading, but Mozilla Firefox blocks the installation..

    https://bayareahot.com/bbs/home.php?mod=space&uid=207999

    February 5, 2021 at 07:18 | Report abuse | Reply
  21. Game Trick

    I am thinking about becoming a 'ProBlogger". I know Blogging is a very slow business, but still i want to know how much time will it take me to start earning at least $100.. I can work everyday for approximately 11 hrs. Can i expect start earning $100 within two months.. Please folks help, give me some idea on how much hard work it's going to be..

    https://gumtreeads.com/user/profile/314653

    February 5, 2021 at 07:20 | Report abuse | Reply
  22. Regulus Game

    How do I export from blogger to wordpress without ruining indexed permalinks?

    https://pbase.com/topics/andersson33melendez/video_games_are_a_great_tool

    February 6, 2021 at 07:13 | Report abuse | Reply
  23. Roblox Tips

    What is a good free blogging website that I can respond to blogs and others will respond to me?

    https://issuu.com/melendez62krag

    February 6, 2021 at 12:02 | Report abuse | Reply
  24. Fortnite Tips

    I have three blogs on tumblr under the same email address. How do I delete one of those blogs without deleting the other two?. Preferably, I'd like someone to answer whom has encountered this problem before and solved it without deleting their other blogs.. Thanks!.

    https://atkinshesselberg96.mystrikingly.com/blog/you-can-be-everything-a-warrior-singer-plumber-or-hedgehog-when-playing

    February 6, 2021 at 18:47 | Report abuse | Reply
  25. Game Info

    I want to start to put all my photos up on my camera, and start a blog or something. Where is a good place to do this like a website or something, do i have to copyright them thanks :).

    https://setiweb.ssl.berkeley.edu/beta/team_display.php?teamid=1422736

    February 6, 2021 at 18:50 | Report abuse | Reply
  26. Game Tips

    How to become a tutor in creative writing for Further education and or teach English as a second language?

    https://wanelo.co/kofodatkins06

    February 6, 2021 at 18:53 | Report abuse | Reply
  27. Game Tips

    What is the best absolutely free blog/web or search engine directory on the web?

    https://www.goodreads.com/user/show/129760689-ottosen

    February 6, 2021 at 18:56 | Report abuse | Reply
  28. Game Trick

    I was planning on starting the guide with wordpress..

    http://www.authorstream.com/fyhnbeasley56/

    February 6, 2021 at 19:04 | Report abuse | Reply
  29. Fortnite Tips

    How often will Facebook check for a new LiveJournal blog post to import to my notes?

    https://dribbble.com/richter71donaldson

    February 6, 2021 at 23:45 | Report abuse | Reply
  30. Fortnite Tips

    I'm looking to spike my journalistic career and thought that a blog might be a good idea. But I also know that there are ways to set up a paypal account attached to the blog for payment to read it or donate. I guess I was inspired by the movie Julia and Julie and I want to do it on my own. Any ideas on how to get started?.

    https://martinussen87villarreal.wordpress.com/2021/02/05/its-amazing-where-picture-games-throw-departed-today-they-started-with-bombastic-consoles-which-took-cartridges-and-looked-mistily-comparable-hand-haggard-cartoons-today-they-let-in-hd-video-opp/

    February 7, 2021 at 09:02 | Report abuse | Reply
  31. Game Trick

    What blog sites would be good for a small business in floral and gifts?

    http://www.authorstream.com/geertsen81monrad/

    February 7, 2021 at 09:04 | Report abuse | Reply
  32. Coin Master Tips

    What can be the ideal Joomla template for a magazine or feature wire service?

    http://daf.csulb.edu/cgi-bin/rd.pl?u=https://regulusgame.com/

    February 8, 2021 at 01:17 | Report abuse | Reply
  33. Game

    There so many different computer tech stuff like Computer Programming, Computer Support Specialists, Computer Systems Analysts. I just want to know what it would be to go work on computers like store or business computers mess up or like tearing computer apart and repairing them. what would them be called?.

    https://dribbble.com/richter71donaldson

    February 8, 2021 at 05:15 | Report abuse | Reply
  34. Coin Master Tips

    Someone said that you had to buy a domain, or your blogs weren't seen by everybody, is that true? Do you know what a domain is? IF not do not answer please..

    http://courses.cs.tau.ac.il/0368-3458/forum/index.php?qa=user&qa_1=kofodhesselberg84

    February 8, 2021 at 10:52 | Report abuse | Reply
  35. Roblox Tips

    I know that there are probably millions of bloggers out there. I also know that there a small percentage of them make money from blogging. Does anyone out there do this, (make money from blogging) and how do they do it?.

    http://courses.cs.tau.ac.il/0368-3458/forum/index.php?qa=user&qa_1=kofodhesselberg84

    February 8, 2021 at 10:54 | Report abuse | Reply
  36. Roblox Tips

    How does a computer virus getting formed?. I have a lot of computer viruses lately but thanks to Norton Anti-virus and Malwarebytes Anti-malware my computer is 100 secure. But how does a computer virus formed? Do people actually make it and they spread it throughout the internet?. . Please tell me more about computer viruses cuz I don't know to much about it I just get rid of them..

    https://www.fcc.gov/fcc-bin/bye?https://regulusgame.com/

    February 8, 2021 at 10:57 | Report abuse | Reply
  37. Coin Master Tips

    Is there NON-Computer Science MS courses available in USA universities for a student with computer background?

    https://issuu.com/melendez62krag

    February 8, 2021 at 10:59 | Report abuse | Reply
  38. Coin Master Tips

    i know you write in it but what else?. what are some good websites to start a blog and what topics should i do?.

    https://bbs.now.qq.com/home.php?mod=space&uid=651682

    February 8, 2021 at 11:05 | Report abuse | Reply
  39. Fortnite Tips

    Can I move a secondary Tumblr blog to a different account?

    https://www.evernote.com/shard/s691/sh/0042ea66-c8b0-7064-2e44-f8536dd866e8/603628edc441953dbabbba4c33dee679

    February 8, 2021 at 14:44 | Report abuse | Reply
  40. Game Info

    I have a blog on blogger and I want to add a background image. How do I do that? And the image is from the internet on my flickr account. So how?.

    http://www.pearltrees.com/ditlevsen51fink

    February 8, 2021 at 14:45 | Report abuse | Reply
  41. Roblox Tips

    How can I get Firefox 3 to stop logging me out everytime I close the browser?

    https://www.treasury.gov/cgi-bin/redirect.cgi/?https://regulusgame.com/

    February 8, 2021 at 22:05 | Report abuse | Reply
  42. Roblox Tips

    I need to start a website what needs to be dynamic in regards to content and ability to run auctions and connect to payments functionalities. Can anyone advised of a suitable application / ISP/Hosting/ practical guides to allow me to under take this progress.. . Regards. . Khalidnz.

    https://coub.com/weekskelly46

    February 8, 2021 at 22:07 | Report abuse | Reply
  43. ClarkTauts

    j77rm enjjd lhtj

    February 28, 2021 at 18:51 | Report abuse | Reply
1 2

Post a comment


 

CNN welcomes a lively and courteous discussion as long as you follow the Rules of Conduct set forth in our Terms of Service. Comments are not pre-screened before they post. You agree that anything you post may be used, along with your name and profile picture, in accordance with our Privacy Policy and the license you have granted pursuant to our Terms of Service.

Advertisement
About this blog

Get a behind-the-scenes look at the latest stories from CNN Chief Medical Correspondent, Dr. Sanjay Gupta, Senior Medical Correspondent Elizabeth Cohen and the CNN Medical Unit producers. They'll share news and views on health and medical trends - info that will help you take better care of yourself and the people you love.