Prows Lab
Spontaneous Mutants

Spontaneous Mutants

With the constant breeding that goes on in the colony, we occasionally discover interesting spontaneous mutations that can be followed up to fix, map and/or characterize the new trait.
During the construction of one of our congenic lines on an A/J background, we recently identified a new spontaneous mutation that leads to right-sided heart failure, with a majority of the mice that are homozygous for the recessive mutation dying between 9 and 18 weeks of age. To more easily maintain and study this line, we are currently trying to identify an early diagnostic marker/measure that predicts outcome and determine whether the mutation is within or outside of the congenic region. Gene identification and specific mutation will be pursued.
Using a phenotype-driven breeding approach, we are close to capturing a “high bleeding time” trait in homozygosity for several lines of inbred mice. Once fixed, we will set out to map the loci and identify the critical gene(s).
We identified a single mouse with a greyish-tan coat color and ruby red eyes in one of our C57BL/6J-derived congenic lines for the ozone project. The substituted A/J-derived congenic region was eliminated and the color coat regenerated, demonstrating that the mutation was not in the congenic interval. This color coat mutation is now on a pure C57BL/6J background. We are now generating an F2 population with A/J mice to map the trait and determine whether this is worthy of further analysis. The F2 population has at least 6 different coat colors, rather than the expected 3 coat colors from a typical cross of A/J and C57BL/6J strains (i.e., black, white and brown).