In the waggler spontaneous mutation, an allelic variant of stargazer, the expression of brain-derived neurotrophic factor is selectively absent in the cerebellar granule cells. The cytoarchitecture of the waggler cerebellum appears to be normal at the light microscope level. The mutant mice exhibit no sensory deficits to auditory stimuli or heat-induced pain. However, they are massively impaired in classic eye-blink conditioning. The waggler allele causes a great variation in spike-wave discharge activity depending on the individual mouse.
The waggler mutation arose spontaneously on the MRL/MpJ-Tnfrsf6lpr background in the laboratory of Dr. Charles Sidman in 1988. This mutation was backcrossed to C57BL/6J via backcross-intercross and the lpr mutation was removed from the strain. Ovary transplantation from homozygous females was used when it became necessary. In 1991 N6 heterozygotes were bred together to generate embryos for cryopreservation.
|Gene Symbol and Name||Cacng2, calcium channel, voltage-dependent, gamma subunit 2|
|Strain of Origin||MRL/MpJ-Faslpr/J|
|General Note||Waggler is a second recessive mutation at the Cacng2 locus that arose in 1988 in the MRL/MpJ-Tnfrsf6 colony maintained at The Jackson Laboratory by Dr. Charles Sidman. Mutant homozygotes are characterized by whole body tremor, an unstable gait, and growth retardation. Hydrocephaly occurs occasionally. Hearing tests by Dr. Lawrence Erway of the University of Cinncinnati showed that the mutant was not deaf. Both sexes breed; no gross neuroanatomical or histopathologic lesions have been found (J:14313).|
|Molecular Note||The phenotype of the waggler is associated with aberrant splicing residing in the first intron. Like the stargazer allele, a RT-PCR analysis demonstrated that in addition to aberrant transcripts, some normally spliced mRNA was detected, suggesting that this mutation does not represent a complete null allele.|
When maintaining a live colony, these mice can be bred as homozygous females to heterozygous males. In our colony, homozygous males did not breed.
When using the waggler mouse strain in a publication, please cite the originating article(s) and include JAX stock #001883 in your Materials and Methods section.