Navigation Links
New study suggests ALS could be caused by a retrovirus
Date:3/2/2011

A retrovirus that inserted itself into the human genome thousands of years ago may be responsible for some cases of the neurodegenerative disease amyotrophic lateral sclerosis (ALS), also known as Lou Gherig's disease. The finding, made by Johns Hopkins scientists, may eventually give researchers a new way to attack this universally fatal condition.

While roughly 20 percent of ALS cases appear to have a genetic cause, the vast majority of cases appear to arise sporadically, with no known trigger. Research groups searching for a cause of this so-called sporadic form had previously spotted a protein known as reverse transcriptase, a product of retroviruses such as HIV, in ALS patients' serum samples, suggesting that a retrovirus might play a role in the disease. However, these groups weren't able to trace this reverse transcriptase to a specific retrovirus, leaving some scientists in doubt whether retroviruses are involved in ALS.

Seeking to verify whether a culprit retrovirus indeed exists, Avindra Nath, M.D., a professor of neurology at the Johns Hopkins University School of Medicine, and colleagues examined brain samples from 62 people: 28 who died from ALS, 12 who died from chronic, systemic diseases such as cancer, 10 who died from accidental causes and 12 who had another neurodegenerative disease, Parkinson's disease, at the time of their deaths. Using a technique known as polymerase chain reaction, the researchers searched for messenger RNA (mRNA) transcripts from retroviruses, a chemical signature that retroviruses were active in these patients.

In samples from the ALS and chronic disease patients, the search turned up mRNA transcripts that came from human endogenous retrovirus K (HERV-K). This retrovirus is one of thousands that became a part of the human genome after infecting our ancestors long ago. Nowadays, these retroviruses are no longer contagious, but are instead passed along through inheritance in part of the genome that scientists consider "junk" DNA.

When Nath and his colleagues took a closer look at the mRNA, they saw that the transcripts seemed to originate from different parts of the genome in the samples from ALS and systemic disease patients. The transcripts also came from different tissues in the brain. While patients with ALS tended to have HERV-K transcripts present in areas surrounding the motor cortex of the brain the area affected by the disease the other patients' transcripts were spread more diffusely through the brain.

Although the researchers express caution, the findings, reported in the January Annals of Neurology, suggest that HERV-K might be the ALS retrovirus that researchers have been looking for.

"This paper doesn't establish causation beyond the level of doubt, but it does provide some promising links between HERV-K and ALS," Nath says. "We've never found a putative retrovirus for this disease before, so this opens up a whole new area."

He and his colleagues plan to study whether HERV-K might cause neuronal damage, a step closer to linking this retrovirus to ALS. They also plan to study what factors may cause HERV-K to reactivate in some people and lead to ALS symptoms. Researchers might eventually be able to fight ALS, Nath adds, using antiretroviral drugs specific to HERV-K.


'/>"/>

Contact: Christen Brownlee
cbrownlee@jhmi.edu
410-955-7832
Johns Hopkins Medical Institutions
Source:Eurekalert

Related biology news :

1. Long-term study shows effect of climate change on animal diversity
2. £2 million study to reveal workings of dementia genes
3. New study looks to define evangelicals and how they affect polling
4. CU-Boulder study suggests air quality regulations miss key pollutants
5. Researchers study acoustic communication in deep-sea fish
6. Study reveals homeowner perceptions in fire-prone areas
7. Researchers study how pistachios may improve heart health
8. Study: urban black bears live fast, die young
9. New study indicates link between weight gains during pregnancy and dieting history
10. Study reveals specific gene in adolescent men with delinquent peers
11. Sweat it out: UH study examines ability of sweat patches to monitor bone loss
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/3/2016)... --> --> ... Fingerprint Identification System Market by Component (Hardware and Software), ... Finance, Government, Healthcare, and Transportation) and Geography - Global ... expected to be worth USD 8.49 Billion by 2020 ... 2020. The transformation and technology evolution from the manual ...
(Date:2/3/2016)... , Feb. 3, 2016 ... addition of the "Emotion Detection and ... Learning, and Others), Software Tools (Facial Expression, ... End Users,and Regions - Global forecast to ... --> http://www.researchandmarkets.com/research/d8zjcd/emotion_detection ) has announced ...
(Date:2/2/2016)... 2016 This BCC Research report provides ... reviewing the recent advances in high throughput ‘omic ... field forward. Includes forecast through 2019. ... and opportunities that exist in the bioinformatic market. ... as well as IT and bioinformatics service providers. ...
Breaking Biology News(10 mins):
(Date:2/9/2016)... ... February 08, 2016 , ... Net-Translators, an industry-leading provider of ... its revamped and improved website. In an on-going effort to further educate customers ... better communicate how the company designs and delivers thorough, high-quality results for its ...
(Date:2/9/2016)... ... February 09, 2016 , ... The publishing industry has been ... is one of the popular publication models that has received wider acknowledgement from ... 3000+ International Conferences across the globe, OMICS International is all set ...
(Date:2/9/2016)... and LONDON , February 9, ... leading bio tech replace paper and protect ... web-based electronic laboratory notebook (ELN) will be rolled out in ... paper-based research and development (R&D) and protect valuable IP. Users ... and follow a specific researcher or experiment as part of ...
(Date:2/8/2016)... /PRNewswire/ - BIOREM Inc. (TSXV: BRM) ("Biorem" or "the Company") ... clean technology companies in the TSX Venture 50 TM . ... on the TSX Venture Exchange, in each of five major ... & life sciences, diversified industries and technology – based ... on investment, market cap growth, trading volume and analyst coverage. ...
Breaking Biology Technology: