Ncbi Length Search

Question

[Nicolas Rosewick]

Hi,

Is it possible to specify the nucleotide length limit in a ncbi search ? I don't find anything on the NCBI website about this ?

Thanks,

N.

[Larry_Parnell]

Is this for a nucleotide similarity search? Or for a search for an entry in a nucleotide database?

Answer 1

[Damian Kao]

You can specify various options in the Entrez Query field to search against subset of the database. Here is a description of the field: http://www.ncbi.nlm.nih.gov/BLAST/blastcgihelp.shtml#entrez_query

For example to limit search against entries that are between 500 to 1000 base pairs/residues you would type into the Entrez Query field: 500:1000[slen]

[Neilfws]

DK has the correct answer. Here's a list of Entrez databases and the fields on which they can be searched: http://dl.dropbox.com/u/1304874/entrez/index.html. You can get this information using the EInfo tool: http://eutils.ncbi.nlm.nih.gov/corehtml/query/static/einfo_help.html.