Hereford (*/he)

s/s + modifiers (k10 complex)
W/+ + modifiers

"With the exception of fox varieties, a mouse of any standardized colour, with as symmetrical as possible white blaze on the face, with the tip rising not higher than in between the ears and not lower than above the eyes, breaking under the chin. Feet stops are required, but not running into the belly markings. Tail stop to be half of the tail's lenght. The belly stop to be even, covering at least third of the belly, stretching from between the front legs and running down in between hind legs. The belly spot is not to run into face or feet markings, being restricted only to the belly. The belly is not to be confusable with Fox, being not as wide.

White to be pure and devoid of any coloured spots or markings, the coloured back and sides to be devoid of any white spots. Eye colour to be as in standardized variety."

Breeding information below the pictures.

LHA cinnamon hereford young.

b, ow. and pic. Mari Martiskainen.

Ideal hereford.

Note: a fox belly is not allowed on a hereford mouse.

Quick Look

Hereford is the "other half" of an older standard for berkshire, which proved to be trying to cover two different markings. This unworking (provisional) standard was split into a hereford, white bellied hereford and head and belly spotted berkshire. The genetics of the variety is rather uncertain, but the article on hereford deals with the W-theory, while this looks at the s-theory.

The s-theory

It is theorized, that berkshire is one of the many recessive white spotting gene (s) varieties, with different outcomes defined by different sets of modifiers. The possible "culprit" is a k-complex (k10) gene C3HeB/FeJLe (k10C3H), which causes white blazes, belly spots and partly white tails. On the top of the mouse, the gene dominates the Mayer-gene (k10Mayer) of the same locus. Mayer causes white spots on the back (and no blazes).

Two hereford mice can produce hereford and "spotted" mice, as the modifiers differentiate, but spotted even/broken mice do not produce hereford without the he-determinants

Sometimes mice without white spotting background can produce offspring with only a belly spot, but no other markings. These mice are possibly heterozygous for k-complex recessives without s/s. That is, S/* k10Mayer/k10Mayer can sometimes cause odd belly spots.