Ophn1^tm1Bill

A loxP flanked hygromycin resistance cassette was inserted into exon 9 of this X chromosome gene. Chimeric male mice were mated with Cre-recombinase transgenic female mice to remove the selection cassette. The remaining loxP site caused a frameshift mutation and a premature STOP codon. Hemizygous males expressed no protein as determined by Western blots on brain and liver extracts. (J:124943)