DNA晶片原理
Microarray arrayer in the Laboratory
DNA Microarray
-Gene expression analysisGCA T ACCA
CGT A T GGT
CGT A T GGT
GCA T ACCA
Principle of Microarray Technology
Gene Sequence/genomic DNA
----------AGTCTTACGACTGAACTG---------Target
Probe
transcription
mRNA
---------AGUCUUACGUCUGAACUGAAAAAA
1. Probe design
Reverse transcription
cDNA
2. Oligo synthesis
3. Microarray printing
TCAGAATGCAGACTTGTCTTTTTT
4. Probe Immobilization
1. Fluorescent labeling *
2. Hybridization
*
*
*
*
TCAGAATGCAGACTTGTCTTTTTT
| | | | | || | | |
CTTACGACTG
Patrick Brown’s Approach
• Use robot to spot glass slides
• Able to measure qualitatively relative
expression levels of genes
– Differential expression by use of simultaneous,
two-color fluorescence hybridisation
• Cheaper with DIY ($60,000)
• Also called home-made system
Born: September 23, 1954, Washington
Affymetrix’s GeneChip
- Photolithography (光罩法) -
基因表現圖譜 (Gene expression profile):
•「基因表現」是「基因作用」的訊號
• 可作為「細胞狀態」的指標
• 是連結基因型態(Genotype)與表徵型態(Phenotype)
的重要關鍵
Multiclass cancer
diagnosis using tumor
gene expression
signatures
PNAS
December 18, 2001 vol. 98 no. 26 15149–15154
Sridhar Ramaswamy*†, Pablo Tamayo*, Ryan Rifkin*‡, Sayan Mukherjee*‡, Chen-Hsiang
Yeang*§, Michael Angelo*, Christine Ladd*, Michael Reich*, Eva Latulippe¶, Jill P. Mesirov*,
Tomaso Poggio‡, William Gerald¶, Massimo Loda†, Eric S. Lander*,**, and Todd R. Golub*††‡‡
*Whitehead Institute Massachusetts Institute of Technology Center for Genome Research, Cambridge,
MA 02138; Departments of †Adult and ††Pediatric Oncology, Dana–Farber Cancer Institute Harvard
Medical School, Boston, MA 02115; Department of Pathology, Brigham and Women’s Hospital, Boston,
MA 02115; ¶Department of Pathology, Memorial Sloan–Kettering Cancer Center, New York, NY 10021;
and Departments of **Biology, ‡McGovern Institute, Center for Brain and Computational Learning, and
§Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139