McGill researchers develop breakthrough technique for genomic analysis of long DNA molecules
Researchers from McGill University and the Génome Québec Innovation Centre have achieved a technical breakthrough that should result in speedier diagnosis of cancer and various pre-natal conditions.
The key discovery, which is described online this week in the Proceedings of the National Academy of Sciences (PNAS), lies in a new tool developed by Professors Sabrina Leslie and Walter Reisner of McGill's Physics Department and their collaborator Dr. Rob Sladek of the Génome Québec Innovation Centre.
It allows researchers to load long strands of DNA into a tunable nanoscale imaging chamber in ways that maintain their structural identity and under conditions that are similar to those found in the human body.
This newly developed "Convex Lens-Induced Confinement" (CLIC) will permit researchers to rapidly map large genomes while at the same time clearly identifying specific gene sequences from single cells with single-molecule resolution, a process that is critical to diagnosing diseases like cancer.
CLIC, the new tool, can sit on top of a standard inverted fluorescence microscope used in a university lab. The innovative aspect of CLIC lies in the fact that it allows strands of DNA to be loaded into the imaging chamber from above, a process which allows the strands of DNA to maintain their integrity.
Existing tools used for genomic analysis rely on side-loading DNA under pressure into nanochannels in the imaging chamber, a practice that breaks the DNA molecules into small pieces, making it a challenge to reconstruct the genome.
"It's like squeezing many soft spaghetti noodles into long narrow tubes without breaking them," explains Prof. Leslie as she describes what it is like to use CLIC. "Once these long strands of DNA are gently squeezed down into nanochannels from a nanoscale bath above, they become effectively rigid which means that we can map positions along uniformly stretched strands of DNA, while holding them still. This means diagnostics can be performed quickly, one cell at a time, which is critical for diagnosing many pre-natal conditions and the onset of cancer."
"Current practices of genomic analysis typically require tens of thousands of cells worth of genomic material to obtain the information we need, but this new approach works with single cells," says Dr. Rob Sladek of the Génome Québec Innovation Centre. "CLIC will allow researchers to avoid having to spend time stitching together maps of entire genomes as we do under current techniques, and promises to make genomic analysis a much simpler and more efficient process."
"Nanoscale physics has so much to offer biomedicine and diagnostics," adds Prof. Leslie. "CLIC brings the nanoscale regime to the bench top, and genomics is just the beginning".
To read the full article "Convex Lens-Induced Nanoscale Templating" by Sabrina R. Leslie et al in PNAS: http://www.pnas.org/cgi/doi/10.1073/pnas.1321089111
To contact the researchers directly: email@example.com
Katherine Gombay | Eurek Alert!
Two decades of training students and experts in tracking infectious disease
27.11.2015 | Hochschule für Angewandte Wissenschaften Hamburg
Increased carbon dioxide enhances plankton growth, opposite of what was expected
27.11.2015 | Bigelow Laboratory for Ocean Sciences
Planet Earth experienced a global climate shift in the late 1980s on an unprecedented scale, fuelled by anthropogenic warming and a volcanic eruption, according to new research published this week.
Scientists say that a major step change, or ‘regime shift’, in the Earth’s biophysical systems, from the upper atmosphere to the depths of the ocean and from...
The Fraunhofer Institute for Solar Energy Systems ISE has installed 70 photovoltaic modules on the outer façade of one of its lab buildings. The modules were...
Nerve cells cover their high energy demand with glucose and lactate. Scientists of the University of Zurich now provide new support for this. They show for the first time in the intact mouse brain evidence for an exchange of lactate between different brain cells. With this study they were able to confirm a 20-year old hypothesis.
In comparison to other organs, the human brain has the highest energy requirements. The supply of energy for nerve cells and the particular role of lactic acid...
In laser material processing, the simulation of processes has made great strides over the past few years. Today, the software can predict relatively well what will happen on the workpiece. Unfortunately, it is also highly complex and requires a lot of computing time. Thanks to clever simplification, experts from Fraunhofer ILT are now able to offer the first-ever simulation software that calculates processes in real time and also runs on tablet computers and smartphones. The fast software enables users to do without expensive experiments and to find optimum process parameters even more effectively.
Before now, the reliable simulation of laser processes was a job for experts. Armed with sophisticated software packages and after many hours on computer...
Researchers at Heidelberg University have devised a new way to study the phenomenon of magnetism. Using ultracold atoms at near absolute zero, they prepared a...
25.11.2015 | Event News
17.11.2015 | Event News
21.10.2015 | Event News
27.11.2015 | Press release
27.11.2015 | Life Sciences
27.11.2015 | Materials Sciences