This spontaneous, dominant vestibular mutation causes heterozygotes to display head tossing, mild circling phenotype, elevated ABR thresholds, and an increased propensity to develop otitis media.Read More +
The variable circling mutation (Varc) is dominant and causes heterozygotes to display head tossing, mild circling phenotype, elevated ABR thresholds compared with their wild-type siblings or C3H/HeJ controls, and increased propensity to develop otitis media. Because C3H/HeOuJ is less susceptible to otitis media than C3H/HeJ, which has a missense mutation in TLR4, Varc was backcrossed onto the C3H/HeOuJ background for 9 generations, but no distinct phenotypic differences were detected in the congenic, indicating that otitis media is not the primary lesion in Varc heterozygotes. This mutation mapped to Chromosome 10, likely between D10Mit194 and D10Mit95.
The Varc mutation arose spontaneously in the C3H/HeJ inbred strain at The Jackson Laboratory when that inbred was at generation F226. After several generations of being maintained coisogenic on C3H/HeJ this dominant mutation was backcrossed onto C3H/HeOuJ and sperm was cryopreserved from heterozygous males at generation N9.
|Allele Name||variable circling|
|Allele Type||Spontaneous (Not Specified)|
|Gene Symbol and Name||Varc, variable circling|
|Strain of Origin||C3H/HeJ|
|Molecular Note||This heritable phenotype arose spontaneously in C3H/HeJ at The Jackson Laboratory and was mapped to Chromosome 10.|