cdsToTranscript {ensembldb} | R Documentation

## Map positions within the CDS to coordinates relative to the start of the transcript

### Description

Converts CDS-relative coordinates to positions within the transcript, i.e. relative to the start of the transcript and hence including its 5' UTR.

### Usage

    cdsToTranscript(x, db, id = "name")

### Arguments

`x` | `IRanges` with the coordinates within the CDS. Coordinates are expected to be relative to the transcription start (the first nucleotide of the transcript). The Ensembl IDs of the corresponding transcripts have to be provided either as `names` of the `IRanges`, or in one of its metadata columns.
`db` | `EnsDb` object.
`id` | `character(1)` specifying where the transcript identifier can be found. Has to be either `"name"` or one of `colnames(mcols(prng))`.

### Value

`IRanges` with the same length (and order) than the input `IRanges` `x`. Each element in `IRanges` provides the coordinates within the transcripts CDS. The transcript-relative coordinates are provided as metadata columns. `IRanges` with a start coordinate of `-1` is returned for transcripts that are not known in the database, non-coding transcripts or if the provided start and/or end coordinates are not within the coding region.

### Author(s)

Johannes Rainer

### See Also

Other coordinate mapping functions: `genomeToProtein`, `genomeToTranscript`, `proteinToGenome`, `proteinToTranscript`, `transcriptToCds`, `transcriptToGenome`, `transcriptToProtein`

### Examples

    library(EnsDb.Hsapiens.v86)
    ## Defining transcript-relative coordinates for 4 transcripts of the gene
    ## BCL2
    txcoords <- IRanges(start = c(4, 3, 143, 147), width = 1,
        names = c("ENST00000398117", "ENST00000333681",
        "ENST00000590515", "ENST00000589955"))

    cdsToTranscript(txcoords, EnsDb.Hsapiens.v86)

    ## Next we map the coordinate for variants within the gene PKP2 to the
    ## genome. The variants is PKP2 c.1643DelG and the provided
    ## position is thus relative to the CDS. We have to convert the
    ## position first to transcript-relative coordinates.
    pkp2 <- IRanges(start = 1643, width = 1, name = "ENST00000070846")

    ## Map the coordinates by first converting the CDS- to transcript-relative
    ## coordinates
    transcriptToGenome(cdsToTranscript(pkp2, EnsDb.Hsapiens.v86),
        EnsDb.Hsapiens.v86)

[Package ensembldb version 2.6.8 Index]