HbSS-Townes MGI:3790753 -1400-gamma-beta<S> Humanized sequence|Inserted expressed sequence http://identifiers.org/mgd/MGI:3790753 Hbb<hbetas> Hbb<tm2(HBB*)Tow> Hbb<tm2(HBG1,HBB*)Tow> targeted mutation 2, Timothy Townes