🪽 White Patterns

Tobiano (TO)

Tobiano is a dominant white pattern gene that creates smooth, rounded white patches that often cross the topline.

Inheritance & Expression

Characteristics

• Rounded white patches
• White legs
• White crossing over the topline
• Dark head with normal facial markings

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Then literally repeat the same structure for:

Splashed White (SW)

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Sabino (SB)

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Frame Overo (O)

Since O/O is lethal, there is no expressive category for homozygous horses because they won't survive.

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Tovero

Tovero is not a separate gene.

A Tovero horse inherits both Tobiano and one or more Overo-type pattern genes.

Common Combinations

• Tobiano + Frame Overo
• Tobiano + Splashed White
• Tobiano + Sabino
• Tobiano + Multiple Overo Genes

Characteristics

Tovero horses commonly display:

• Tobiano body markings
• Extensive facial white
• Blue eyes
• Irregular body patterns
• Mixed pattern characteristics

Because Tovero is a combination rather than a single gene, no two Toveros look exactly alike.

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White (W20)

Instead of being a visible pattern itself, W20 increases the expression level of other white patterns.

Examples:

• Minimal → Medium
• Medium → Expressive

A horse carrying W20 may produce larger markings than a horse with the same pattern but without W20.

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Then Appaloosa should work differently:

Leopard Complex (LP)

LP determines whether a horse can display Appaloosa characteristics.

Inheritance

PATN1

PATN1 controls how much white patterning develops.

Example Outcomes

Roan (RN)

Roan is a dominant pattern gene that mixes white hairs evenly throughout the body while typically leaving the head and lower legs darker.

Inheritance