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Upon E3 ' deletion , the locus became rapidly silenced and lost positive histone epigenetic marks , and the mature B cells partially dedifferentiated , induced RAG - 1 and - 2 along with certain other pro - B cell makers , and then redifferentiated after triggering Ig lambda gene rearrangements .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
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