POLYMORPHISM OF ACUTE-PHASE SERUM AMYLOID-A ISOFORMS AND AMYLOID RESISTANCE IN WILD-TYPE MUS MUSCULUS CZECH

Until CE/J mice and their offspring were characterized as amyloid-resi stant, all mice were thought to be amyloid-susceptible to multiple inj ections of azocasein or a single injection of silver nitrate following administration of amyloid enhancing factor. We now report, for the fi rst time, that wild-type Mus musculus czech and Fl hybrids bred by cro ssing M. musculus czech with amyloid-susceptible CBA/J mice are also a myloid resistant. Based on the derived amino acid sequences of two ser um amyloid A (SAA) cDNA clones, we describe two unusual SAA gene isofo rms in M. musculus czech, one of which differs from four previously ch aracterized acute-phase apoSAA isoforms at several amino acid residues . Our findings support the hypothesis that protection against amyloid fibril formation in wild-type M. musculus czech mice and their offspri ng is linked to apoSAA gene mutations (molecular motif). (C) 1996 Acad emic Press, Inc.