Ttr^{tm3(TTR*)Kymm}

ES cells containing the Ttrtm1Kymm null allele that serves as acceptor in recombination mediated cassette exchange were electroporated with a replacement vector and a cre recombinase expression vector. The replacement vector consisted of a variant human TTR cDNA and a FRT-flanked puromycin resistance gene flanked by a lox66 and a loxP site. The variant sequence encodes a Methionine at position 30 instead of a Valine (V30M). Human but not mouse TTR protein was detected in the liver and serum of homozygote mice by immunoblot assays. (J:146510)