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Question: blastn for selected database and/or organism
0
5 months ago by
aush20
United States
aush20 wrote:

Is there any way to blast my nucleotide sequence only against specific NCBI database, for example, refseq_rna?

Similarly, I'd like to limit my search to a specific organism/taxid.

As I understand, blastSequences() doesn't have these options now. Is there any other solution?

modified 5 months ago by James W. MacDonald48k • written 5 months ago by aush20
1
5 months ago by
United States
James W. MacDonald48k wrote:

Note that blastSequences is just doing a query to the NCBI blast API, as noted in the help page for the function. Because of that, you can only make the queries that are amenable to the API. You can for example query on a different database (again, as noted in the help page):

>  blastSequences(x = "GGCCTTCATTTACCCAAAATG", database = "reseq_rna")
estimated response time 45 seconds
list()

But there isn't any facility, so far as I can tell, to specify the organism.

Thank you James! I have contacted NCBI support, and the solution turned out to be quite simple: besides QUERY, their API supports a field ENTREZ_QUERY. Unfortunately it is not included in annotate for now, but I simply added &ENTREZ_QUERY=human%5borgn%5d string to my QUERY, and this worked!