I am trying to use the topGO package but I get this error message "Error in .local(.Object, ...) : allGenes must be a named vector" when I execute the following command.

# Data preparation of reference dataset
selGenes <- genefilter(fitted, filterfun(pOverA(0.20, log2(100)), function(x) (IQR(x) > 0.25)))
eSet <- fitted[selGenes, ]
AllNames <- rownames(eSet)
head(AllNames)
as.factor(AllNames)

## My genes of interest
IntGenes <- read.csv("D1D0_genes2.csv", header = TRUE) # 2-fold or more
## Convert dataframe to matrix with row and column names
IntGenes2 <- IntGenes[,-1]
rownames(IntGenes2) <- IntGenes[,1]
GeNamen <- rownames(IntGenes2)
head(GeNamen)
as.factor(GeNamen)

## Set up connection to ensembl database
ensembl <- useMart(biomart = "plants_mart", dataset = "bnapus_eg_gene",
                   host = "plants.ensembl.org")
# list the available datasets (species)
listDatasets(ensembl) %>% filter(str_detect(description, "Brassica"))
# specify a data set to use
ensembl = useDataset("bnapus_eg_gene", mart=ensembl)

#Get Ensembl gene IDs and GO terms
GTOGO <- getBM(attributes = c("external_gene_name", 
                              "go_id"),
                              mart = ensembl)
head (GTOGO)
#Remove blank entries
GTOGO <- GTOGO[GTOGO$go_id != '',]
# convert from table format to list format
geneID2GO <- by(GTOGO$go_id,
                GTOGO$external_gene_name,
                function(x) as.character(x))
# examine result
head(geneID2GO)

GOdata <- new("topGOdata",
              description = "GO analysis of 1 dpi vs mock",
              ontology = "BP",
              allGenes = AllNames,
              geneSel = GeNamen,
              annot = geneID2GO,
              nodeSize = 5)

I looked at the Ensembl annotations and noticed that the gene names that are commonly used in publications correspond to "external_gene_name" not the "ensembl_gene_id". Is this why it is not working? Do I have to access the "ensembl_gene_id"?

Thank you,

Henrik

The short answer is that you need to read the error message. It says that allGenes has to be a named vector. This is referring to your object AllNames. Is AllNames a vector? Is it a named vector?

It's often instructive when working with topGO, which has IMO suboptimal help pages, to do things like

library(topGO)
data(geneList)
head(geneList)
1095_s_at   1130_at   1196_at 1329_s_at 1340_s_at 1342_g_at 
1.0000000 1.0000000 0.6223795 0.5412240 1.0000000 1.0000000

To see what the data used in the vignette look like, so you can emulate that.