compareHPSets {PCAN} | R Documentation

## Compare 2 sets of HP terms based on semantic similarity

### Description

This function compares each couple of HP terms from each of the 2 provided sets based on Information Content (IC)

### Usage

    compareHPSets(hpSet1, hpSet2, IC, ancestors, method = "Resnik",
      BPPARAM = bpparam())

### Arguments

`hpSet1` | a set of HP terms
`hpSet2` | another set of HP terms
`IC` | a named vector of Information Content by HP term
`ancestors` | a named list of ancestors by HP term
`method` | the method for computing semantic simalirity among those available in `calcHpSim` (default: "Resnik" returns the IC of the MICA: Most Informative common ancestor)
`BPPARAM` | An optional `BiocParallelParam` instance defining the parallel back-end to be used during evaluation (used internally by the `bpmapply` function).

### Value

A matrix of semantic similarity

### Author(s)

Patrice Godard

### See Also

`calcHpSim`

### Examples

    ## Prerequisite
    data(geneByHp, hp_descendants, package="PCAN")
    geneByHp <- unstack(geneByHp, entrez~hp)
    ic <- computeHpIC(geneByHp, hp_descendants)

    ###########################################
    ## Use case: comparing a gene and a disease
    data(traitDef, geneDef, hp_ancestors, hpDef, package="PCAN")
    omim <- "612285"
    traitDef[which(traitDef$id==omim),]
    entrez <- "57545"
    geneDef[which(geneDef$entrez==entrez),]
    ## Get HP terms associated to the disease
    data(hpByTrait, package="PCAN")
    hpOfInterest <- hpByTrait$hp[which(hpByTrait$id==omim)]

    ## Get HP terms associated to the gene
    hpByGene <- unstack(stack(geneByHp), ind~values)
    geneHps <- hpByGene[[entrez]]
    ## Comparison of the two sets of HP terms
    compMat <- compareHPSets(
        hpSet1=geneHps, hpSet2=hpOfInterest,
        IC=ic,
        ancestors=hp_ancestors,
        method="Resnik",
        BPPARAM=SerialParam()
    )
    ## Get the symmetric semantic similarity score
    hpSetCompSummary(compMat, method="bma", direction="symSim")
    bm <- hpSetCompBestMatch(compMat, "b")
    hpDef[match(c(bm$compared, bm$candidate), hpDef$id),]
    ## Assessing the significance of this score by comparing to all other genes
    hpGeneResnik <- compareHPSets(
        hpSet1=names(ic), hpSet2=hpOfInterest,
        IC=ic,
        ancestors=hp_ancestors,
        method="Resnik",
        BPPARAM=SerialParam()
    )
    hpMatByGene <- lapply(
        hpByGene,
        function(x){
            hpGeneResnik[x, , drop=FALSE]
        }
    )
    resnSss <- unlist(lapply(
        hpMatByGene,
        hpSetCompSummary,
        method="bma", direction="symSim"
    ))
    candScore <- resnSss[entrez]
    hist(
        resnSss,
        breaks=100, col="grey",
        ylim=c(0,300),
        xlab=expression(Sim[sym]),
        ylab="Number of genes",
        main=paste(
            "Distribution of symmetric semantic similarity scores\nfor all the",
            length(resnSss), "genes"
        )
    )
    polygon(
        x=c(candScore, 10, 10, candScore),
        y=c(-10, -10, 1000, 1000),
        border="#BE0000",
        col="#BE000080",
        lwd=3
    )
    withHigher <- sum(resnSss >= candScore)
    text(
        x=candScore, y=mean(par()$usr[3:4]),
        paste0(
            withHigher, " genes (",
            signif(withHigher*100/length(resnSss), 2), "%)\n",
            "show a symmetric semantic\n",
            "similarity score greater than\n",
            "the gene candidate for\n",
            "for the HPs under focus."
        ),
        pos=4,
        cex=0.6
    )

[Package PCAN version 1.20.0 Index]