Navigation Links
New NIST SRM helps improve diagnosis of Huntington's disease
Date:4/14/2011

A new Standard Reference Material (SRM) from the National Institute of Standards and Technology (NIST) will help clinical genetics labs accurately diagnose Huntington's disease, an inherited degenerative brain disorder that usually begins between ages 35 and 50 and progressively leads to physical impairment, dementia and death. A person whose mother or father developed Huntington's disease has a 50-50 chance of getting the currently incurable disease.

Huntington's disease results from a genetic mutation affecting approximately one in 10,000 persons. The mutation is characterized by an excessive number of repeats of a sequence of three nucleotides (the chemical building blocks of DNA), cytosine-adenine-guanine (CAG), located on the fourth of the 23 pairs of chromosomes found in every human cell. Since 1993, a genetic test has been available to count the number of CAG "triplet repeats" that exist, determining if a person will develop Huntington's disease, and if so, how severe it will be.

Individuals with up to 26 repeats are normal. Individuals with 27 to 35 repeats also are unaffected, but the number of repeats can increase in their children. Individuals with 36 to 39 repeats may or may not develop symptoms of Huntington's disease; however, if they do, it will likely be at a much later onset and slower progression than more pronounced cases. Individuals with 40 or more repeats will definitely be affected, while individuals with 60 or more repeats will develop symptoms in childhood.

Electing to be tested for Huntington's disease is an extremely difficult choice. Since a positive diagnosis undoubtedly will affect decisions about careers, relationships, having children and other life events, there is no room for error. But errors can occur sometimes because the test requires making many copies of the patient's DNA using the polymerase chain reaction (PCR), the standard technique for "amplifying" or making multiple copies of a DNA molecule. On rare occasions, PCR creates extraneous CAG repeatsan anomaly known as "stutter"that make the triplet count appear higher than it really is.

Measures of the overall length of the DNA moleculeand in turn, the CAG repeat countare greatly improved when the new NIST reference, SRM 2393, "CAG Repeat Length Mutation in Huntington's Disease," is used as a quality control. The SRM consists of six samples of DNA measured and certified by NIST for triplet repeats ranging in number from 15 to 75. The certified values are free of stutter, providing genetic screeners a more viable standard with which to compare a patient's DNA sample.

SRM 2393 joins more than 50 reference materials produced by NIST for quality control in clinical testing. It also is the latest response by NIST to the call from the health care community for higher-order reference materials for genetic diagnostic tests (the last being an SRM to improve the accuracy of Fragile X syndrome diagnoses). Standard Reference Materials are among the most widely distributed and used products from NIST. The agency prepares, analyzes and distributes about 1,300 different materials that are used throughout the world to check the accuracy of instruments, validate test procedures and serve as the basis for quality control standards worldwide.


'/>"/>

Contact: Michael E. Newman
michael.newman@nist.gov
301-975-3025
National Institute of Standards and Technology (NIST)
Source:Eurekalert  

Related medicine news :

1. Hormone Helps You Sniff Out Food, Study Finds
2. New educational booklet helps patients prepare for a colonoscopy
3. New warm line helps clinicians tackle patients substance abuse
4. In trial, video helps people weigh bariatric surgery pros, cons
5. MIT biologists pinpoint a genetic change that helps tumors move to other parts of the body
6. Grant helps UT Southwestern researcher study causes of preterm birth
7. New tool helps surgeons predict patients risk of complications after bariatric operations
8. Internet program reduces infant and toddler sleep problems, helps moms sleep better too
9. Mayo Clinic researchers find cardiac pacing helps epilepsy patients with ictal asystole
10. New targeted drug helps smokers stub it out
11. Surgical technique helps adult male survivors of childhood cancer regain fertility
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
New NIST SRM helps improve diagnosis of Huntington's disease
(Date:2/13/2016)... ... February 13, 2016 , ... In the early or “honeymoon” stage of a ... go out of their way to be romantic, and may exaggerate a strength or ... any online dating profile. , A recent study from Queendom.com , however, ...
(Date:2/12/2016)... WA, and Washington, DC (PRWEB) , ... ... ... PATH and the Siemens Foundation today announced a new initiative—the Siemens Foundation-PATH ... for low-resource settings. The partnership will recruit top students from U.S. universities ...
(Date:2/12/2016)... ... , ... As a former television executive, owner Tal Rabinowitz knows how stressful ... decompress, Rabinowitz found herself drawn to a casual meditation class while working at NBC ... implementing a 20-minute-per-day meditation practice with her team. After her tenure at NBC, she ...
(Date:2/12/2016)... (PRWEB) , ... February 12, 2016 , ... Every winter, ... , This winter the West Penn Burn Center, part of the Allegheny ... #1, to bring you the “Space Heaters Need Space” campaign. , ...
(Date:2/12/2016)... ... 12, 2016 , ... Erlanger Agency has announced a new partnership in its ... campaign focuses on the fight against breast cancer, fundraising for a local woman named ... . , Carmen is a loving single mother of two boys who also serves ...
Breaking Medicine News(10 mins):
(Date:2/11/2016)... 11, 2016 The primary goal of this ... patterns on the usage of liquid biopsy. Key information ... - Timeframe of liquid biopsy adoption amidst future ... Evs—by organization type - Sample inflow to conduct liquid ... stool, serum, and so on. - Correlation analysis of ...
(Date:2/11/2016)... 11, 2016 Laboratory glassware and ... laboratories. These may range from microscope slides to large ... made from borosilicate glass because of its low weight ... other hand, started gaining popularity over the past decade ... replace glass with plastic in several applications due to ...
(Date:2/11/2016)... DUNKIRK, N.Y. , Feb. 11, 2016  Governor ... Athenex that will create 1,400 jobs throughout ... by a partnership with the SUNY Polytechnic Institute, includes ... the Conventus Building in Buffalo , ... square foot manufacturing facility in Dunkirk ...
Breaking Medicine Technology: