DNA MicroArray Image Processing Case Study
by Robert Bemis
22 Oct 2002
(Updated 19 Aug 2010)
Case study used in Biomedical and Image Processing seminars (highlights algorithm development).
|
Watch this File
|
| File Information |
| Description |
In one type of gene expression analysis, fluorescently tagged messenger RNA from different cells are hybridized to a microscopic array of thousands of complimentary DNA spots that correspond to different genes. Illuminated spots emit different color light, indicating which genes are expressed (e.g., green=control, red=sample, yellow=both).
In this case study, MATLAB, the Image Processing and Signal Processing toolboxes were used to determine the green intensities from a small portion of a microarray image containing 4,800 spots. A 10x10 pattern of spots was detected by averaging rows and columns to produce horizontal and vertical profiles. Periodicity was determined automatically by autocorrelation and used to form an optimal length filter for morphological background removal. A rectangular grid of bounding boxes was defined. Each spot was individually addressed and segmented by thresholding to form a mask. The mask was used to isolate each spot from surrounding background. Individual spot intensity was determined by integrating pixel intensities. Finally, integrated intensities were tabulated and saved to a data file for subsequent statistical analysis to determine which genes matter most.
With the MATLAB code and example image in this package you can follow the steps used for this application. |
| Required Products |
Image Processing Toolbox
Signal Processing Toolbox
|
| MATLAB release |
MATLAB 7 (R14)
|
|
Tags for This File
|
| Everyone's Tags |
|
| Tags I've Applied |
|
| Add New Tags |
Please login to tag files.
|
| Comments and Ratings (17) |
| 06 Jan 2012 |
Helen Chen
|
|
|
| 21 Feb 2011 |
B.K. Mishra
|
|
|
| 29 Dec 2010 |
Esteban A. Vidal
|
|
|
| 26 May 2009 |
Leo T
|
|
|
| 07 Oct 2007 |
Saeed Arshad
|
|
|
| 29 Mar 2007 |
Danie John
|
|
|
| 04 Jun 2006 |
M Mehta
|
|
|
| 27 Mar 2006 |
ABHISHEK TRIPATHI
|
|
|
| 19 Nov 2005 |
Luigi Rosa
|
|
|
| 15 Jul 2005 |
Hadi Hosseinzadegan
|
|
|
| 16 May 2005 |
ali haider
|
|
|
| 02 May 2005 |
Haig Djambazian
|
|
|
| 11 Mar 2005 |
anvesh reddy
|
|
|
| 18 Feb 2005 |
Vibhor Maheshwari
|
|
|
| 01 Dec 2004 |
maheswar gunampally
|
|
|
| 22 Apr 2004 |
howard li
|
|
|
| 26 Mar 2004 |
amol ingole
|
|
|
| Updates |
| 12 Aug 2004 |
Algorithm more robust. Problem solution more complete by measuring spot intensity for both color planes and computing expression levels. Update also highlights new Publish capabilities of MATLAB 7. |
| 19 Aug 2010 |
copyright |
|
Contact us