Mice homozygous for the vestibulomotor degeneration spontaneous mutation (Atp8a2wl-vmd) can be identified at 20 days of age by their small size, shaky behavior, ungroomed coat, and emaciation. Homozygous mutant mice tend to sit hunched with rear feet and limbs tucked in towards the body and exhibit a generalized tremor. When startled, they jump sideways. They clasp their hind feet when picked up by the tail. Most mutants die by 30 days of age, probably from inability to feed and starvation. There is no apparent difference between the wabbler lethal (wl) and vestibulomotor degeneration mutant phenotypes.
The Vestibulo-Motor Degeneration (vmd, now Atp8a2wl-vmd) mutation arose in a C3H/H2SnJ colony at the Jackson Laboratory in 1987.
|Allele Name||wabbler lethal vestibulomotor degeneration|
|Gene Symbol and Name||Atp8a2, ATPase, aminophospholipid transporter-like, class I, type 8A, member 2|
|Strain of Origin||C3H/HeSnJ|
|Molecular Note||A 9167 bp deletion removes exon 32. This results in a 32 amino acid deletion in the ninth transmembrane domain.|