Stability of gene expression in postmortem brain revealed by cDNA gene array analysis.

We utilized nylon arrays to measure gene expression in mouse brains after various postmortem intervals (PMIs). Gene expression after overnight refrigeration or 4 h at room temperature then overnight refrigeration correlated highly and approximately equivalently to that in brains processed immediately. After 8-24 h at room temperature and overnight refrigeration gene expression correlation and equivalency declined, but 90-95% of detected genes were within +/-40% of baseline levels. Brain homogenate pH did not change with PMI.