To determine the role of Zfhx1b in the development of the basal ganglia, we used a conditional mutagenesis approach. Using an allele of Zfhx1b, in which exon 7 is floxed (Higashi et al., 2002), we removed Zfhx1b expression using two different Cre alleles. Deletion of exon 7 creates a frameshift mutation and premature truncation of the protein. Previous analysis failed to detect the truncated mutant protein in Zfhx1b mutant tissues, providing evidence that this is a null allele (Higashi et al., 2002).
