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Three of the short ORFs in the central region of BIV have been identified by location and structural similarity to the nonstructural / regulatory genes ( vif , tat , and rev ) of other lentiviruses ; we also discovered two unique ORFs , termed W and Y , which may serve as exons for novel genes .
 GENE: vif; GENE: tat; GENE: rev
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: vif; GENE: tat; GENE: rev