Infidus

The infidus locus determines whether or not stripy white markings that strongly resemble a partial pliohippus evorsus phenotype appear on the head and neck, rump, or both. When creating a custom horse (or using the custom previewer), the user is asked to select the specific genotype at the infidus locus, rather than choosing a phenotype and having the game select an appropriate genotype.

## Alleles

There are three infidus alleles, with various dominance relationships and a strong island correlation.

### if

Found on all isles of Paradisus, the if allele is dominant with respect to If and If+ and is by far the most common. It does not confer any white markings upon the character. When the infidus locus is homozygous for if, it is not displayed in the genetics section of the horse's page. It can be obtained using a drop gene item and selecting 'Infidus (head)' or 'Infidus (butt)' as appropriate depending on the horse's present infidus genotype.

### If

Found only on Ternio, the If allele is recessive with respect to if and co-dominant with respect to If+, and, if not counteracted by an if allele, causes white stripes to appear on the head and neck. It is inactive in mules and donkeys, and has no visible effect when it occurs in a horse that also has a hypohippus evorsus phenotype. It can be obtained using an Add A Gene: Infidus (Head) item.

### If+

Found only on Ternio, the If+ allele is recessive with respect to if and co-dominant with respect to If, and, if not counteracted by an if allele, causes white stripes to appear on the rump. It is inactive in mules and donkeys, and has no visible effect when it occurs in a horse that also has a Miocene-influenced evorsus phenotype. It can be obtained using an Add A Gene: Infidus (Butt) item.

## Phenotypes

### Non-Infidus (ifif, Ifif, If+if)

The non-infidus phenotype is simply a lack of the white stripes typically associated with the infidus locus. Donkeys and mules always appear to have this phenotype, regardless of infidus genotype.

### Half-Evorsus (Head) (IfIf)

The half-evorsus (head) phenotype, usually just called half-evorsus, consists of a series of white stripes on the neck and head of a horse, these being perpendicular to the spine and largely to the snout, respectively. Some stripes toward the forehead and above the eyes may be arranged in a less orderly fashion. This phenotype is never seen on mules or donkeys, regardless of infidus genotype, and is hidden by a hypohippus evorsus phenotype.

### Half-Evorsus (Rump) (If+If+)

The half-evorsus (rump) phenotype, usually just called half-evorsus, consists of a series of white stripes on a horses rump, running perpendicular to the spine at first before continuing down each thigh, perpendicular to the line of the leg. This phenotype is never seen on mules or donkeys, regardless of infidus genotype, and is hidden by a hypohippus evorsus phenotype.

### Half-Evorsus (Head and Rump) (If+If)

The half-evorsus (head and rump) phenotype, also usually just called half-evorsus, consists of the all the stripes usually seen on the half-evorsus (head) and half-evorsus (rump) phenotype combined on the same horse. This phenotype is never seen on mules or donkeys, regardless of infidus genotype, and is hidden by a hypohippus evorsus phenotype.