Exons 11 and 12 were replaced with a 2.2 kb genomic region that contains an additional cytosine at position 2939 in exon 11 followed by a stop codon. This insertion results in the amino acid substitution of leucine with proline at position 980 (L980P) followed by a premature termination. This mutation is associated with Crohn's disease in humans (3020iC, L1007insC). (J:157879)