Col-I 2.3 (139)|Col I-2.3-tTA(139) transgene insertion 139, Robert Nissenson O transgene Transgene Col I-2.3-tTA(139) Tg(Col1a1-tTA)139Niss Col-I 2.3 (139) http://identifiers.org/mgd/MGI:3852098 MGI:3852098