A dominant-negative allele, recapitulating the human SALL1 1277-1278delGA mutation, was generated by inserting a stop codon and a floxed neo cassette into the exon 2. The deleted region corresponded with nt 1300-3443 of the cDNA. A truncated protein was detected by Western blot analyis of homozygous mutant embryonic tissue using an N-terminal antibody. (J:85458)