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Involvement of a second lymphoid-specific enhancer element in the regulation of immunoglobulin heavy-chain gene expression .
 DNA: immunoglobulin heavy-chain gene; DNA: lymphoid-specific enhancer element
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:
 DNA: immunoglobulin heavy-chain gene; DNA: lymphoid-specific enhancer element