Genetics

Glossary

Tiny Dictionary Terminology

While the Finnmouse's Site's Genetics section presupposes the reader to have a basic understanding of how genetics work, here's a tiny glossary to make sure we're all on the same page.

Alleles etc

Allele - An allele is what a fancier usually calles a "gene". I have tried to be consistant in my terminology and keep the language in "fancier mode" and talk about "genes" instead of "alleles". However, due to the sheer amount of articles in the genetics section, there's bound to be some slips of the tongue. I apologize for this.

Gene - In fancier's parlance, a gene is one of the members of a locus. Each mouse has two genes in each of its loci.

Locus, loci - Group of genes, belonging together. All genes in a same locus are marked with the same letter, which is either capital or small and can have upper case letters as further identification. There can be a large number of genes in each group all in all, but each individual being always has only two (and always two!) of all the genes in the same group.

Series - Here, simply another name for "locus", which consists of a series of genes all belonging to the same group.

Dominances and Whatnot

Dominance, dominant - Genes have "hierarchies" within their own locus, their group. The different genes of a locus aren't equal, some are more important when it comes to having their effect show than others. A gene is dominant, when it can hide the effect of another gene.

Recessiveness, recessive - When a gene is recessive (see above), it's effects will show only when there's two of the same gene present.

Semidominance, semidominant -

Incomplete dominance - Sometimes, the genes aren't fully recessive, or fully dominant and the effects of two different recessives of the same locus both show trough. Himalayan is a good example of this: the mouse has c^h/c and the resulting colour is in between c^h/c^h and c/c.

Carrying - A mouse (or any other critter, for that matter) is said to "carry" a gene, when a fully dominant gene is paired with a fully recessive one in a locus. Thus, an A/a Agouti mouse 'carries' black, but an A/A Agouti does not. Only recessives can be carried! Remember, when a mouse is of a diluted variety, it does not carry full colour. a/a p/p (Dove) mouse does not carry black - it is genetically a black mouse, only diluted. This is an important distinction to make.

Full, Diluted?

Full colour - The pigment has not been reduced in intensity by any diluting gene.

Diluted colour - The pigment has been reduced in intensity (that is, has been changed lighter) by the effect of a diluting, pigment intensity reducing gene.

Capital vs. Small Letter etc

Capital letter (like "A") - When a gene has been given a capital letter symbol (like "A"), it means that the gene in question is dominant over genes with small letter symbols (like "a"). The letters have to be the same ones for the dominance/recessiveness to hold true, it's about relationships within a group. For example P is not dominant over d, but is dominant over p.

Lower case letter (like "a") - When a gene has been given a small letter symbol (like "a"), it means that the gene in question is recessive to genes with capital letter symbols (like "A"). Otherwise, see above.

Upper case letters - Using upper case letters is a way of marking genes belonging to the same group and is used when there are more than two genes existing all in all. So, you can see from the gene's name that, say, c^ch belongs to the c-locus.

/* - The second gene in a pair is not known, because it's effects are 'hidden' by the first one. For example P/P and P/p look the same.

Colour Terms: Top, Tip, Base, Basic...

Top colour - The colour on the mouse's upper side. Basically, the colour you can see when you look at the mouse from above.

Undercolour, base colour - When the mouse's hair consists of different layers of colours, one on top of another, the undercolour is the nearest one to the mouse's skin.

Tip colour, tipping - When the mouse's hair consists of different layers of colours, one on top of another, the top colour is the uppermost one. Logically, at the tip of the hair.

Ticking - Uniformly coloured guard hairs, usually darker (see silvering), on a non-self mouse.

Silvering - White, silver-coloured or white-and-silver coloured guard hairs in the mouse's coat.

Basic colour - On a tan or fox variety, basic colour is the top colour. On a colour/white marked variety, where there's less colour than white, basic colour is the white area (i.e. capped). On a variety with more colour than white (say, banded), basic colour is the non-white area.