What problem does it solve? Bulk RNA-seq count matrices from featureCounts carry raw Ensembl IDs or transposable-element IDs that are unusable for downstream differential expression and GSEA until they are annotated, and annotating after filtering irreversibly loses those IDs. This Skill routes the annotation step between counting and DE so gene symbols and TE Subfamily:Family:Class labels are attached correctly and edgeR DGEList objects are assembled. ## Core Features & Use Cases - Gene-symbol annotation: Map Ensembl IDs to gene symbols via Ensembl/biomaRt or org.db, aggregate duplicate stripped IDs, and build a gene DGEList with provenance tracking. - Transposable-element annotation: Parse TE IDs into Subfamily:Family:Class, build a combined gene+TE DGEList, and export family- and class-level GMT genesets for GSEA. - Use Case: You receive a featureCounts gene matrix and a TE count matrix from STAR/featureCounts preprocessing; use this Skill to annotate both, row-bind them into one combined DGEList, and hand off TE GMT files to downstream GSEA. ## Quick Start Annotate my bulk RNA-seq featureCounts count matrix with gene symbols via biomaRt and build an edgeR DGEList before filtering.