featureFilter: Annotation-based Filtering of Features (CpG sites) in a...

Description Usage Arguments Value Author(s) References See Also

Description

Features with insufficient annotation carry little value for the subsequent data analysis. The function featureFilter provides options of filtering features (CpG sites) from a MethyLumiSet (or MethyLumiM) object based on available annotation data.

Usage

1
2
3
4
5
featureFilter(eset, require.entrez=FALSE,
    require.GOBP=FALSE, require.GOCC=FALSE,
    require.GOMF=FALSE, exclude.ChrX=FALSE,
    require.closeToTSS=FALSE, range.DistToTSS=c(-500, 300),
    require.CpGisland=FALSE, ...)

Arguments

eset

A MethyLumiSet or MethyLumiM object.

require.entrez

If TRUE, filter out features without an Entrez Gene ID annotation.

require.GOBP, require.GOCC, require.GOMF

If TRUE, filter out features whose target genes are not annotated to at least one GO term in BP, CC and MF ontology, respectively.

exclude.ChrX

If TRUE, filter out features in chromosome X to avoid gender effect.

require.closeToTSS

If TRUE, filter out features that are not close to transcription start site (TSS). Features without annotation of distance to TSS will also be removed. Can only used for GoldenGate platform.

range.DistToTSS

Ignored if require.colseToTSS is FALSE. A vector of numeric values of length 2, indicating the range of tolerable distance from transcription start site (TSS) in basepair (bp). If require.clostToTSS is TRUE, features whose distance to TSS falls outside this designated range will be removed. The default value is c(-500, 300), where -500 represents the distance to TSS from the left and 300 the distance from the right.

require.CpGisland

If TRUE, filter out features that are not in CpG islands.

...

Unused, but available for specializing methods.

Value

The function featureFilter returns a list consisting of:

eset

The filtered MethyLumiSet or MethyLumiM object.

filter.log

A list giving details of how many probe sets where removed for each annotation-based filtering step performed.

Author(s)

Chao-Jen Wong cwon2@fhcrc.org

References

R. Bourgon, R. Gentleman, W. Huber, Independent filtering increases power for detecting differentially expressed genes, PNAS, vol. 107, no. 21, pp:9546-9551.

See Also

nsFilter


seandavi/methylumi documentation built on Oct. 28, 2021, 12:42 a.m.