This strain is homozygous for the retinal degeneration allele Pde6brd1.
The human Branchio-Oto-Renal Syndrome is generally a dominant disorder with incomplete penetrance and variable expressivity resulting from null mutations in the EYA1 gene. The mouse Eya1bor allele is primarily a recessive hypomorphic mutation. Nevertheless, homozygous mice with this hypomorphic allele offer a good model for Branchio-Oto-Renal Syndrome. The phenotype of Eya1bor/Eya1bor mice parallels that of the human Branchio-Oto-Renal Syndrome and both are thought to result from reduced gene dosage. The Eya1bor/Eya1bor mice are deaf and their behavior is marked by circling and head-bobbing. They lack all but the most basal one-quarter of the cochlea, and the organ of Corti is completely absent. They have foreshortened, narrower semicircular canals and in some the common crus is incomplete. Their kidneys are absent or dysmorphic with greater severity generally on the left side. Fewer homozygotes than expected are born. During mapping crosses using CAST/Ei and C3H/HeJ, it was found that genetic background impacts both the kidney and inner ear phenotypes, and modifier genes in humans also may impact the severity of Branchio-Oto-Renal-Syndrome.
The branchio otorenal syndrome mutation (Bor) arose spontaneously on the C3HeB/FeJ inbred strain at The Jackson Laboratory in 1984, when that inbred was at generation F123. This mutant subline was maintained by sibling inbreeding heterozgyotes with wild type siblings for over a decade then backcrossed twice to C3HeB/FeJ with intervening sibling inbreeding. Between 1997 and 1998 embryos were cryopreserved from C3HeB/FeJ females bred to heterozygous males at generation F29N2.
|Allele Name||branchio otorenal syndrome|
|Gene Symbol and Name||Eya1, EYA transcriptional coactivator and phosphatase 1|
|Strain of Origin||C3HeB/FeJ|
|Molecular Note||Insertion of an intracisternal A particle (IAP) element in intron 7. The presence of the IAP insertion was associated with reduced expression of the normal mRNA and aberrant splicing.|
When using the branchio otorenal syndrome mouse strain in a publication, please cite the originating article(s) and include JAX stock #002588 in your Materials and Methods section.