This recessive spontaneous mutation causes head tossing, circling, otitis media, hearing impairment, abnormal hair pattern, curled tail, reduced fertility, reduced in utero viability, and smaller body size.Read More +
Curly tail bobber homozygotes may display head tossing, circling, otitis media, hearing impairment, abnormal hair pattern, curled or wavy tail or small size in comparison to littermates. The fur, most noticeably on the rump, can grow in reverse orientation leading to an overall ruffled coat appearance. The phenotype varies from animal to animal, may include only small body size and wavy tail, and the head bobbing and circling phenotypes range from severe to mild. Homozygotes seldom breed, although they do live a normal lifespan. Histology on two males found testicular atrophy, giant nuclei in the epididymis, and mild hydrocephalus. Histology focused on the ears found otitis media in all ears assessed from six weeks to six months of age and ABR analysis found moderate to severe hearing loss as early as five-and-a-half weeks of age, the earliest time point assessed. No hearing loss or abnormal phenotype was found in heterozygotes. Heterozygous intercrosses yielded fewer than 15% homozygotes.
The culy tail bobber 2 Jackson mutation arose spontaneously in the CBy.A-Ttc7fsn/J strain and was crossed once to C57BL/6J and then maintained by sibling intercrossing. The mutant founder of this line did not have the Ttc7fsn homozygous phenotype and that phenotype did not present in more than a decade of sibling intercrossing so it is believed to be absent from this line. Sperm was cryopreserved from heterozygous males and recovery was successful using BALB/cByJ oocytes.
|Allele Name||curly tail bobber 2 Jackson|
|Allele Type||Spontaneous (Not Specified)|
|Gene Symbol and Name||Celsr1, cadherin, EGF LAG seven-pass G-type receptor 1|
|Strain of Origin||CByJ.A-Ttc7fsn/J|
|Molecular Note||This spontaneous mutation failed a complementation test with the first curly tail bobber mutation proving the two allelic|