A floxed neo cassette and T796G mutation in exon 20 were inserted via homologous recombination. Cre-mediated recombination removed the neo cassette. This mutation enlarges the ATP binding pocket and allows specific inhibition by 4-amino-1-tert-butyl-3-(1'-naphthylmethyl)pyrazolo[3,4-d]pyrimidine. (J:261265)