Mice homozygous for the shaker with no syndactylism spontaneous mutation (Slc12a2sy-ns) is allelic with the original radiaton-induced shaker-with-syndactylism mutation (sy). Homozygous mutant mice exhibit deafness and balance defects but have a normal foot morphology. Two other spontaneous alleles of sy, fused phalanges and fused phalanges 2 Jackson, do not affect hearing or behavior. Tests for allelism among mice with four different mutant alleles at the shaker-with-syndactylism locus (sy, syfp, syfp-2J, and Slc12a2sy-ns) indicate that sy is a deletion including at least two genes associated with distinct phenotypes. Mice homozygous for sy have syndactylous feet and other skeletal malformations, are deaf, and exhibit abnormal behavior characteristic of vestibular dysfunction. Complementation test results indicate that sy, syfp and syfp-2J are alleles of the same gene, but that Slc12a2sy-ns is an allele of a different gene.
Shaker with no syndactylism (sy-ns) appeared in the offspring from frozen embryo parents of the microcytic anemia strain MK/ReJ x C57BL/6J (stock #002097) in 1993. Heterozygous or forced heterozygous sibling pairs were mated until generation F8 and then a backcross was made to C57BL/6J followed again by sibling matings. An F2 homozygote was then backcrossed to C57BL/6J and backcrossing was continued in the cross-intercross method to N4 to eliminate the microcytic anemia mutation (Slc11a2mk) from the stock. The shaker with no syndactylism stock was cryopreserved in 2001 by mating heterozygous males at generation N4F1 to C57BL/6J females.
|Allele Name||no syndactylism|
|Gene Symbol and Name||Slc12a2, solute carrier family 12, member 2|
|Strain of Origin||MK/ReJ x C57BL/6J|
|General Note||This allele fails to complement the sy locus but does complement the fused plalanges alleles. Therefore, the original sy deletion includes both the gene responsible for deafness (Slc12a2) and the gene responsible for abnormal foot morphology.|
|Molecular Note||Nucleotide insertion at position 2955 located in exon 21 causes a frameshift and a premature stop codon.|
Although most homozygous females breed, when maintaining a live colony, heterozygous mice may be bred together.
When using the no syndactylism mouse strain in a publication, please cite the originating article(s) and include JAX stock #002757 in your Materials and Methods section.