Apob^tm1.1Zc

Deletion of nucleotide 5449 in exon 26 and a loxP-flanked PGK-neo cassette inserted into intron 24 were introduced to the gene via homologous recombination. This deletion mimics the ApoB-38.9 truncation mutation found in human familial hypobetalipoproteinemia (FHBL). The neo cassette was removed by transient expression of Cre recombinase in correctly targeted ES cells. Southern blot analysis confirmed the absence of the neo cassette in homozygous mutant mice; Western blot analysis showed a mutant protein product of similar size to the human ApoB-38.9 mutant protein. (J:65191)