Mbd4^tm1Bird

A cassette, containing a splice acceptor site and IRES-Beta-geo, was inserted into intron 1 of the endogenous locus. Northern blot and RT-PCR analysis showed levels of transcript in homozygous mutant mice to be less than 0.1% of those in wild-type mice. Two truncated transcripts were identified; one which truncated at the transgenic polyadenylation signal and another in which a frameshift mutation was introduced by the excision of the IRES-Beta-geo transgenic region (leaving the the splice acceptor site in between exons 1 and 2). (J:77896)