03/12/2025
The Vienna Effect on Rabbit Eyes
The Vienna gene (v) is known for producing Blue-Eyed Whites (BEWs) or rabbits with White marks, but what many breeders don’t realize is how broadly and subtly this gene influences eye pigmentation. Expression ranges from crystal-blue clarity all the way to marbled heterochromia and blue flecks hidden inside an otherwise normal iris.
Below is a breakdown of the most common Vienna eye expressions-all of which can appear in VM (Vienna Marked) Rabbits.
🔹 Clear Crystal Blue
Bright, even, icy blue. This is the classic BEW/Vienna blue with full pigment across the iris.
🔹 Sectoral Heterochromia (Marbled)
Part blue, part brown/grey. The iris has patches or slices of different pigment-one of the strongest indicators of Vienna.
🔹 Violet or “Ruby-Cast Blue”
Seen in chocolates and shaded varieties. Vienna lightens the iris, while base color adds a warm violet or ruby tint.
🔹 Muted Blue
Soft, cloudy, or grey-blue. A lighter Vienna expression without the clarity of BEW blue.
🔹 Blue-Flecked Eyes
Normal iris with small blue spots or streaks. A subtle but sure sign of a Vienna carrier.
🔹 Additional Marbling Example
Shows how Vienna marbling can vary- half-blue eyes, crescent blue slices, or swirled patterns.
🔹 Complete Heterochromia (One Blue Eye, One Brown Eye)
This occurs when the Vienna gene reduces pigment in one iris but not the other, resulting in one fully blue eye and one fully brown or grey eye. It is a strong form of Vienna expression, caused by uneven pigment suppression during eye development. While marbling affects part of an iris, complete heterochromia affects the entire eye-making it one of the clearest indicators that Vienna is present, even in rabbits without any visible white markings.