The spontaneous juvenile alopecia (jal) mutation in mice is associated with the insertion of an IAP element in the Gata3 gene

Abstract Background: A combination of genetic fine-mapping and complementation testing was used previously to assign the juvenile alopecia mutation (abbreviated jal) to the GATA binding protein 3 (Gata3) gene on Chromosome 2 in mice. However, sequence analysis of Gata3 exons (including coding and noncoding regions) revealed no differences between wild type C3H/HeJ and co-isogenic C3H/HeJ-jal/J mutant mice. Results: Using a PCR-based scanning method, here we have tested the hypothesis that jal might result from insertion of a transposable element in or near the Gata3 gene. We show that the jal mutation is specifically associated with an intracisternal A particle (IAP) element of the I∆1 subtype that has transposed to Intron 3–4 in the Gata3 gene, and use the same panel of recombinants used previously to fine-map jal to show that this IAP element and jal are located within the same small genetic interval. Conclusion: Transposition of an IAP element of the I∆1 subtype into Intron 3–4 of the mutant Gata3jal allele is the likely cause of the juvenile alopecia phenotype in mutant mice.