New method identifies working copies of genes in human cells; could improve early diagnosis of sick tissues

In biology, as in real estate, location matters. Working copies of active genes -- called messenger RNAs or mRNAs -- are positioned strategically throughout living tissues, and their location often helps regulate how cells and tissues grow and develop. But to analyze many mRNAs simultaneously, scientists have had to grind cells to a pulp, which left them no good way to pinpoint where those mRNAs sat within the cell.