Wt1^tm1Asc

A T to C mutation at the +2 position of intron 9 and a floxed neo cassette (also in intron 9) were introduced via homologous recombination. The point mutation is found in patients with Frasier syndrome and results in the absence of an alternative splice product coding for the 3 amino acids KTS (the KTS region), between zinc fingers 3 and 4, at the end of the long version of exon 9: only the alternative transcript with the short version of exon 9, without the KTS codons, is expressed. The neo cassette was removed by transient expression of cre recombinase in correctly targeted ES cells. RT-PCR analysis using primers to exons 9 and 10 demonstrated the presence of only -KTS transcripts in homozygous mutant animals. The +KTS transcript is completely absent. (J:71149)