14642
The enhancer for the immunoglobulin mu heavy chain gene ( IgH ) activates a heterologous gene at the pre-B cell stage of B lymphocyte differentiation .
 ( DNA: enhancer, None) , ( DNA: heterologous gene, None) , ( protein: IgH, None) , ( DNA: immunoglobulin mu heavy chain gene, None) , ( cell type: B lymphocyte, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( DNA: enhancer, None) , ( DNA: heterologous gene, None) , ( protein: IgH, None) , ( DNA: immunoglobulin mu heavy chain gene, None) , ( cell type: B lymphocyte, None) 