hgu133aLOCUSID {hgu133a} | R Documentation

## Mappings between probe identifiers and LocusLink identifiers

### Description

LocusLink identifiers are unique ids used by NCBI http://www.ncbi.nlm.nih.gov/LocusLink/ to represent genetic loci and link to curated sequence and descriptive information. hgu133aLOCUSID maps probe identifiers to LocusLink identifiers for genes represented by the probe identifiers.

### Details

Mappings of probe ids to LocusLink ids are achieved through the linkage between probe ids to manufacturer/user provided ids contained in hgu133aACCNUM. LocusLink ids are first mapped to manufacturer/user provided ids using file(s) provided by Locuslink and in some cases UniGene and other available sources and then linked to probe ids based on the mappings between probe ids and manufacturer/user provided ids.

When a given probe id was mapped to different LocusLink ids by different sources, the one agreed by most sources was selected. When no agreement was achieved among sources, the one of the smallest numeric value was selected.

Mappings were based on data provided by:

LocusLink:ftp://ftp.ncbi.nih.gov/refseq/LocusLink/LL_tmpl.gz. Built: January 12, 2005

Package built: Wed Jan 12 22:21:54 2005

### References

http://www.ncbi.nlm.nih.gov

### Examples

        # Convert the environment to a list
        xx <- as.list(hgu133aLOCUSID)
        # Remove probe ids that do not map to any LOCUSID
        xx <- xx[!is.na(xx)]
        if(length(xx) > 0){
            # The LOCUSIDs for the first two elements of XX
            xx[1:2]
            # Get the first one
            xx[[1]]
        }

[Package hgu133a version 1.7.0 Index]