MicroRNAs as biomarkers

In the 1990s, Carlo Croce, then director of the Kimmel Cancer Center in Philadelphia, Pennsylvania, was hunting for genes involved in chronic lymphocytic leukaemia. The disease was consistently associated with a lesion in chromosome 13, and so, back before the human genome was sequenced, his lab determined the identity of the nucleotides in an 800-kilobase stretch from the deleted region and began searching for protein-coding genes. “We failed, for six years,” recalls Croce, now director of the Human Cancer Genetics Program at the Ohio State University in Columbus. His lead graduate student left science to go to business school. Rosetta Genomics is using microarrays and PCR to identify microRNA biomarkers and develop tests.