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A new B-cell-specific enhancer element has been identified 3' of E4 and the octamerlike motifs in the human immunoglobulin heavy-chain gene enhancer .
 protein: human immunoglobulin heavy-chain; DNA: B-cell-specific enhancer element; DNA: human immunoglobulin heavy-chain gene enhancer
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 protein: human immunoglobulin heavy-chain; DNA: B-cell-specific enhancer element; DNA: human immunoglobulin heavy-chain gene enhancer