3882
The mutants were obtained by substitution into a molecular clone of M - MuLV DNA by DNA from two acutely transforming viruses , Ableson MuLV ( Ab - MuLV ) and Moloney murine sarcoma virus ( M - MSV ) .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities:  
Answer:
 None