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HeLa and Jurkat cell lines carrying the nef gene linked to the CMV promoter or the HIV - 1 LTR were isolated by coselection for neomycin resistance .
 GENE: nef gene; GENE: HIV - 1 LTR
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
 GENE: nef gene; GENE: HIV - 1 LTR