The researchers say that their imaging system basically allows them to see cells that have undergone a specific mutation, and thus may be useful in understanding how pre-cancerous mutations arise.
This is the first time that a team of researchers has been successful in pinpointing the number and location of mutant cells in intact tissues, say the researchers who worked with mouse pancreatic cells.
"Understanding where mutations come from is fundamental to understanding the origins of cancer," says Bevin Engelward, associate professor of biological engineering and member of MIT's Center for Environmental Health Sciences.
Engelward joined forces with Peter So, a professor of biological and mechanical engineering, to develop technologies that made it possible to detect clusters of cells that seemed to be descended from the same progenitor cell.
The researchers observed that over 90 per cent of the cells harbouring mutations were within clusters.
They say that that observation suggested that the majority of mutations were inherited from another cell, rather than arising spontaneously in individual cells.
Since the type of mutation being studied occurs at a rate on par with other types of mutations, "it is as if we are peering in at the very general process of mutation formation, persistence and clonal expansion," said Engelward.
"We think this raises the possibility that mutations resulting from cell division are a tremendous factor in increasing the mutagenic load," she said.
During the study, the researchers genetically genetically engineered a strain of mice in which DNA would fluoresce if a mutation occurred in a particular sequence, and then used a high-resolution microscopy technique developed by Professor So to detect individual cells that carried the mutation.
"The problem drove the development of a new imaging technology, which now can be used for lots of things," said Engelward.
A report describing the new study has been published in the online edition of the Proceedings of the National Academy of Science.