How to: Find expression patterns
Two databases at NCBI contain expression data. 1) UniGene offers EST-based expression profiles for gene-oriented clusters of ESTs. These profiles suggest patterns of expression -- by tissue, developmental stage, or health status -- from EST counts in unbiased cDNA libraries. 2) GEO Profiles offers gene expression patterns derived from microarray studies. Each Profile is presented as a chart that displays the expression level of one gene across all samples in a study.
Starting with...
A GENE RECORD (e.g. Human CTRC, GeneID 11330)
- Use a gene name, symbol or identifier number to search the Gene database, or “All Databases” on the NCBI home page.
- In the desired Gene record (such as for human CTRC), follow the UniGene or GEO Profiles links on the right side of the page.
- Upon clicking on UniGene, scroll down to the “EST Profile” link in the Gene Expression section. You can link to GEO Profiles from the UniGene record by using the Links menu in the upper right of the record.
- After clicking on the GEO Profiles link, use the web page to view expression profiles for individual datasets, or use the “Download profile data” button to retrieve the displayed datasets. See the help link, the “?”, next to the download button. You can link to UniGene from GEO Profiles by using the Links menus, or the “Find related data” function under “Profile data.”
A NUCLEOTIDE ACCESSION (e.g. NM_007272, S82198)
- Use the sequence identifier to search “All Databases” on the NCBI home page.
- If UniGene or GEO Profiles has a number to the left (for example: NM_007272 "All Databases" query), click on the either of these databases to go to the results, then follow steps 3 or 4 above.
- Alternatively, click on Nucleotide to display the sequence record (for example: S82198 Nucleotide sequence record). From this record, scroll down to the section in the right-most column named 'All links from this record and click on Gene, UniGene, or GEO Profiles. Then, follow the steps documented above.