This mutation is allelic to a targeted mutation for this gene. Homozygous mice produce approximately 25% of the normal levels of transcript from this allele. RT-PCR analysis demonstrated that no alterations in the coding sequence would result in any alteration of the amino acid sequence. A 5.5 kb retrotransposon-like element is found in intron 1. About 75% of the mRNA produced is an aberrant 6.5 kb form lacking exons 2-6 but containing exon 1. The remaining 25% of the mRNA formed is of normal, 4.4 kb, size. (J:22206, J:56133, J:110573)