Tcf3^tm1Cmu

Insertion of a neomycin resistance cassette into the E12-specific exon disrupted the gene. RT-PCR studies of fetal liver and of lung from 5 week old mice detected trace amounts of E47-specific transcript in homozygous mutant mice. The authors predict that both gene products, E12 and E47, are inactivated in this allele. (J:67011)