3059874 M-MSV Moloney murine sarcoma virus 33 3059877 M-MSV Moloney sarcoma virus 4 3059876 M-MSV murine sarcoma virus 4 3059878 M-MSV Moloney mouse sarcoma virus 2 3059879 M-MSV Moloney MSV 1 3059875 M-MSV murine sarcoma virus, Moloney isolate 1