Recombination of loxP sites that flanked exon 6 resulted in the deletion of these sequences in the germline. Deletion of exon 6 results in a loss of function of the gene by generating a frameshift from exon 5 to exons 7 - 10 with the introduction of a premature stop codon in exon 7. Western blot and qRT-PCR experiments confirmed the absence of expression from this allele.