Satellite Banner
Genomics
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Accurate Detection of Extremely Rare Mitochondrial DNA Deletions Associated with Aging

Published: Thursday, September 05, 2013
Last Updated: Thursday, September 05, 2013
Bookmark and Share
The study published in Aging Cell identifies a new tool to accurately analyze extremely rare mitochondrial DNA deletions associated with a range of diseases and disorders as well as aging.

This approach, which relies on Droplet Digital PCR (ddPCR™) technology, will help researchers explore mitochondrial DNA (mtDNA) deletions as potential disease biomarkers.

The accumulation of mtDNA mutations is associated with aging, neuromuscular disorders, and cancer. However, methods to probe the underlying mechanisms behind this mutagenesis have been limited by their inability to accurately quantify and characterize new deletion events, which may occur at a frequency as low as one deletion event per 100 million mitochondrial genomes in normal tissue. To address these limitations, researchers at the Seattle, Washington-based Fred Hutchinson Cancer Research Center developed a ddPCR-based assay known as "Digital Deletion Detection" (3D) that allows for the high-resolution analysis of these rare deletions.

"It is incredibly difficult to study mtDNA mutations, let alone deletions, within the genome," said Dr. Jason Bielas, Assistant Member of the Public Health Sciences Division at the Fred Hutchinson Cancer Research Center and lead author of the study. "Our 3D assay shows significant improvement in specificity, sensitivity, and accuracy over conventional methods such as those that rely on real-time PCR."

Bielas added, "The increase in throughput afforded by droplet digital PCR shortened the analysis of deletion events to days compared to months using previous digital PCR methods. Without the technology, we could not have made this discovery."

At the center of the study was Bio-Rad Laboratories' QX100™ ddPCR system. Using the QX100 system, Bielas and his team analyzed eight billion human brain mtDNA genomes and identified more than 100,000 genomes with a deletion. They discovered that, contrary to popular belief, the majority of the increase in mtDNA deletions was not caused by new deletions but rather by the expansion of previous deletions. They hypothesized that the expansion of pre-existing mutations should be considered as the primary factor contributing to age-related accumulation of mtDNA deletions.

How the 3D Assay Works
3D is a novel three-step process that includes enrichment for deletion-bearing molecules, single-molecule partitioning of genomes into droplets for direct quantification via ddPCR, and breakpoint characterization using next-generation sequencing.

Once the enrichment process is completed using methods previously developed by Bielas and colleagues, the concentration of molecules within the droplets is adjusted by using the QX100 system so that the majority of droplets contain no mutant genomes while a small fraction contain only one. This process allows each deletion to be amplified without bias and without introducing the artifacts that are common in qPCR.

Following amplification, deletions can be analyzed using ddPCR to determine the absolute concentration of mutated molecules. Using the relationship between droplet fluorescence and amplicon size, Bielas and his team were able to characterize the size and complexity (whether they were a result of a few clonal expansions or a large collection of random deletions) of rare mitochondrial deletions in human brain samples.

The 3D assay provides an important new tool that will allow researchers to better study the mechanisms of deletion formation and expansion, and their role in aging. Droplet digital PCR's high throughput and increased sensitivity will also allow Bielas' lab to target other low-level disease-causing mtDNA deletions in skeletal muscle, brain tissue, and blood.


Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,400+ scientific posters on ePosters
  • More than 3,700+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Awards for Bio-Rad's Protein Expression Products and Genomic Workflow Solutions
BioInformatics LLC has recognized Bio-Rad with two prestigious Life Science Industry Awards for “Best Protein Expression & Analysis Products” and “Best Workflow Solutions — Genomics.”
Monday, January 19, 2015
Droplet Digital PCR Enables Measurement of Potential Cancer Survival Biomarker
Study paves the way for further research into the role of TIL quantification in immunotherapy and as a cancer survival predictor.
Tuesday, December 10, 2013
A Brief RT-qPCR “Field Guide” for MIQE Adherence
Bio-Rad’s Sean Taylor and Eli Mrkusich have published a practical guide for MIQE compliance.
Monday, December 09, 2013
Bio-Rad Announces Mini-Protean Tetra Cell Users Website
The new online social networking site is created for current and new Bio-Rad Mini-PROTEAN® system users.
Wednesday, August 20, 2008
Bio-Rad Launches new Website for Researchers Transfecting Mammalian Cells
Bio-Rad adds ‘Gene Transfer Protocols’ to its Gene Expression Gateway Web-site, dedicated to researchers working with mammalian cells.
Friday, June 27, 2008
Testing Results of the BioOdyssey Calligrapher MiniArrayer for Clinical Research Available
Bio-Rad announces the availability of a technical bulletin describing results of the testing of the BioOdyssey™ Calligrapher™ MiniArrayer.
Thursday, November 08, 2007
Scientific News
RNAi Screening Trends
Understand current trends and learn which application areas are expected to gain in popularity over the next few years.
New Weapon in the Fight Against Blood Cancer
This strategy, which uses patients’ own immune cells, genetically engineered to target tumors, has shown significant success against multiple myeloma, a cancer of the plasma cells that is largely incurable.
Tracking Breast Cancer Before it Grows
A team of scientists led by University of Saskatchewan researcher Saroj Kumar is using cutting-edge Canadian Light Source techniques to screen and treat breast cancer at its earliest changes.
DNA Damage Seen in Patients Undergoing CT Scanning
Along with the burgeoning use of advanced medical imaging tests over the past decade have come rising public health concerns about possible links between low-dose radiation and cancer.
The Mystery of the Instant Noodle Chromosomes
Researchers from the Lomonosov Moscow State University evaluated the benefits of placing the DNA on the principle of spaghetti.
Oxitec ‘Self-Limiting Gene’ Offers Hope for Controlling Invasive Moth
A new pesticide-free and environmentally-friendly way to control insect pests has moved ahead with the publication of results showing that Oxitec diamondback moths (DBM) with a ‘self-limiting gene’ can dramatically reduce populations of DBM.
Web App Helps Researchers Explore Cancer Genetics
Brown University computer scientists have developed a new interactive tool to help researchers and clinicians explore the genetic underpinnings of cancer.
Kiwi Bird Genome Sequenced
The kiwi, national symbol of New Zealand, gives insights into the evolution of nocturnal animals.
Scientists Identify Schizophrenia’s “Rosetta Stone” Gene
Scientists have identified a critical function of what they believe to be schizophrenia’s “Rosetta Stone” gene that could hold the key to decoding the function of all genes involved in the disease.
Yeast Cells Use Signaling Pathway to Modify Their Genomes
Researchers at the Babraham Institute and Cambridge Systems Biology Centre, University of Cambridge have shown that yeast can modify their genomes to take advantage of an excess of calories in the environment and attain optimal growth.
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,400+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,700+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FREE!