Credit: NIGMS
A new technique could enable faster diagnosis of cancer and various prenatal conditions, according to a paper published in Proceedings of the National Academy of Sciences.
The method, known as convex lens-induced confinement (CLIC), 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 in the human body.
CLIC lets researchers map large genomes rapidly and identify specific gene sequences from single cells with single-molecule resolution, a process that is critical to diagnosing diseases like 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,” said study author Rob Sladek, MD, of McGill University in Montreal, Canada.
“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.”
The CLIC imaging chamber can sit on top of a standard inverted fluorescence microscope, and strands of DNA can be loaded into the chamber from above, which allows the strands to maintain their integrity.
Existing tools used for genomic analysis rely on side-loading DNA under pressure into nanochannels in the imaging chamber. This breaks the DNA molecules into small pieces, making it a challenge to reconstruct the genome.
CLIC, on the other hand, is “like squeezing many soft spaghetti noodles into long, narrow tubes without breaking them,” according to study author Sabrina Leslie, PhD, also of McGill University.
“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,” she said.
“This means diagnostics can be performed quickly, one cell at a time, which is critical for diagnosing many prenatal conditions and the onset of cancer.”
