Import gene list to Seurat to define cell types Is there a way to import gene list into Seurat to define cell type? The default cell types in Seurat is not enough for our research. For example, we want to mark a subtype of B cells in Seurat, but seems like Seurat only have general B cell, I'm planning to download gene list from Genomic Cytometry, and then import the gene list into Seurat and then Seurat define cell types in the cluster based on the gene list I import. Does Seurat support this function?
Seurat does not define cell types by name. It clusters and assigns each cell to a cluster, from 0 to X.
If your data has the cell type (e.g. B,T, Mast cells) it means that someone annotate the clusters so that they have a biological meaning.

You can assign different names to the clusters by using the AddMetaData function.

sampleID  cellType
cell1     B
cell2     B
cell3     T
cell4     T

newMeta &lt;- oldMEta
newMeta$origType &lt;- newMeta$cellType
newMeta$cellType &lt;- c("B1","B","Treg","Tkill")

object &lt;- AddMetaData(object, newMeta)


The new metadata should look like 

sampleID  origType  cellType
cell1     B         B1
cell2     B         B
cell3     T         Treg
cell4     T         Tkill


You can then swap the labels using SetAllIdent(object = test, id = "cellType"). Your tSNE or uMAp, will now show the new cell types.

Have a look at Manually define clusters in Seurat and determine marker genes