use of ensemble pep fasta and mapping to gene_symbols

[wolski]

ENSP00000451042.1 has gene_symbol:TRBD1 One gene_symbol can have many ENSPs. Roll up to "gene_symbol".

Solution, Create a new column gene_symbol so that peptide annotation looks like this: protein_Id, gene_symbol, stripped_sequence

Use gene_symbol for protein_Id, then do roll up.