IgH<3H9> targeted mutation 1, Martin Weigert 3H9 sd-tg VH3H9R 3H9 MGI:3513167 http://identifiers.org/mgd/MGI:3513167 3H9R Igh-J<tm1(3H9-VDJ)Mwg> 3H9.KI VH3H9 Tg