Allelic complexes

I’m just starting to learn about allelic complexes and had a thought. I know blue eyed Lucy and black eyed Lucy are allelic complexes and that most of the morphs that produce these are incomplete dominant so it’s possible to have multiple inherited. Would it be possible for the offspring to have both if say the parents were a fire honey and a vanilla butter? I know they couldn’t both be visible unless it’s a paradox because it’s the eyes but just speaking genetically

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Yes, that pairing could produce a Fire Honey Vanilla Butter. I don’t know what that would do to the eye color.

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The eye colour would be blue

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Allelic complexes are groups of different mutations that occur at the same genetic locus (position) on homologous chromosomes. Since each parent contributes one allele per locus, offspring inherit two alleles at each locus, forming combinations that can be homozygous (the same mutation from both parents), heterozygous (one mutation and one wild-type), or heteroallelic (two different mutations at the same locus).

In the example of a Fire Honey paired with a Vanilla Butter, two separate allelic complexes are involved:

•The Fire complex (sometimes called the Black-Eyed Leucistic complex), which includes mutations such as Fire, Vanilla, Sulfur, etc.
•The Blue-Eyed Leucistic (BEL) complex, which includes Butter, Mojave, Honey, etc.

Because these complexes occur at different genetic loci, it is entirely possible for a snake to inherit one allele from each.

•For example, a Fire and Vanilla pairing results in a heteroallelic animal within the Fire complex, often expressed as a Vanilla Cream.
•A Fire and Butter pairing involves one allele from each complex and produces no leucism, but both incomplete dominant traits are expressed.
•A Fire Vanilla Butter, with Fire/Vanilla at the Fire complex and Butter/Normal at the BEL complex, is also genetically valid. This animal would express a bright, high-expression phenotype, but it would not be leucistic.

However, in the case of pairing to create super forms in each complex, such as a Fire/Butter bred to a Fire/Butter, the resulting offspring could be homozygous for both traits. Let’s call this resulting morph “Burnt Toast”

The Burnt Toast animals would carry two leucism-causing alleles at each of two separate loci (homozygous for each complex). In theory, both leucistic pathways would be active. Due to the pigment-suppressing nature of leucism, though, the visual phenotype would still be a completely white snake. Instead of the typical blue or solid black eyes associated with single-complex super forms, these animals would likely have blue-silver or gray eyes, as the expression from both loci is functionally overlapping. Although genetically both complexes are expressed, their effects are not visually additive beyond the overall suppression of pigmentation.

The only time both traits might appear together, but distinct and separate, is in the case of a paradox animal, which is a rare, random form of genetic mosaicism not inherited through standard Mendelian genetics.

In summary, a snake can inherit alleles from both the Fire and Blue-Eyed Leucistic complexes, and if both are in their super form, the offspring will theoretically express both leucistic conditions. However, because both involve pigment suppression, the result is a visually all-white snake with likely blue-silver or pale eyes. The incomplete dominant inheritance pattern still applies, but due to leucism’s suppression of pattern and color, only one overall leucistic phenotype is visible, even though two separate genetic mechanisms are present.