A digital image processing-based system and method for quantitatively
processing a plurality of nucleic acid species expressed in a microarray
are disclosed. The microarray is a grid of a plurality of sub-grids of the
nucleic acid species. The system includes a scanner that has a digital
scanning sensor that scans the microarray and transmits from an output a
digital image of the microarray, and a computer that receives the digital
image of the microarray from the scanner and then processes the digital
image, identifying each of the microarray's sub-grids. The computer
identifies the position of each of the sub-grids by (a) identifying
regions in the digital image that each contains one of the sub-grids, (b)
identifying rows and columns in each region where nucleic acid species are
expressed to form a set of candidate sub-grids in each region, (c)
selecting for each region a probable sub-grid from the set of candidate
sub-grids in each region, and (d) comparing the positions of the probable
sub-grids from each region to finalize the sub-grid positions.
