Genetics

A-locus

8. a^e - Extreme Nonagouti

a^e is the lowest recessive in the a-locus and is recessive to all other genes in the a-locus. It is the last but not least in the series. This gene removes all tan from the mouse.

8.1. Homozygous Forms

a^e/a^e results in a jet black mouse (of course only when there are no dilutes present). "Extreme black" mice are found in the best blacks of English breeders, as well as dark-pointed siameses and himalayans. Some US standards have written separate standards for a^e/a^e mice, calling them "super black" or "extreme black".

Black, ae/ae B/* C/* D/* P/* pic: Anniina Tuura

When an a^e/a^e mouse has diluting genes present, the resulting varieties have deeper and darker colouring when compared to their a/a equivalents as well.

Being the lowest recessive of its locus, a^e is very easy to lose when it is being transferred into new lines and colours. Once you have a^e/a^e mice, you can't mistake them for a/a mice, the difference is that noticeable. The tricky part is telling carriers from non carriers while creating a line.

8.2. Heterozygous Forms

a^e does not show in any of its heterozygous forms.