Homozygotes can be identified by approximately 7 to 8 days of age by the gray coat color distinct from the black coat of their heterozygous and wild-type littermates. They are ataxic and display opisthotonus and convulsions, consistent with other neurological alleles of this gene. Most homozygotes die by 3 weeks of age although some have lived longer.
The nm4272 mutation arose spontaneously at The Jackson Laboratory in 2008 in the strain B6.V-Lepob/J (stock #000632) and was backcrossed further onto the C57BL/6J background. There was no phenotypic evidence of the obese mutation in the first 3 backcross-intercross generations to C57BL/6J indicating that this mutation has been bred out.
|Allele Name||dilute lethal 32 Jackson|
|Gene Symbol and Name||Myo5a, myosin VA|
|Strain of Origin||B6.Cg-Lepob/J|
|Molecular Note||This spontaneous mutation was proven allelic with the dilute mutation by failed complementation in an outcross to DBA/2J.|