Table 1

Advantages and limitations of SAGE and DNA chip technology for analysis of difference in mRNA expression in different tissues

Advantages Limitations
SAGE• Frequency of many transcripts can be determined
•  Efficient
•  Can detect novel genes
•  Can find low abundance transcripts.

•  Largely relies on the availability of sequences representative of genes in the particular target species, usually as expressed sequence tags (ESTs)
•  A lesser proportion of murine genes are available
DNA chip
•  Rapid methods of sample analysis
•  Can handle a lot of samples
•  Polymorphism discovery and its correlation with diseases/drug effects.

•  Databases usually limited to known genes
•  Limited number of sequences that can be loaded onto individual chips (around 10 000 at present)
•  Few chips are available representing different species and difference groups of clones or genes
  • SAGE = serial analysis of gene expression. ESTs = expressed sequence tags.