2459
The most important risk factors are : 1 ) genetic ; 2 ) Epstein - Barr virus ( infectious mononucleosis ) ; 3 ) congenital and acquired immunodeficiency ; 4 ) occupational exposure ( the wood industry ) .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
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