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[Melanins]  [Erythrins]  [Patterns]  [Selection]  [Combos]  [Oddities]  [A-what-istic???]

Pattern genes are those which affect the location, size, or absence/presence of the different markings. Please note that there is no such thing as a "pattern gene" or a "color gene" and these categories are only used for our convenience. Most pattern genes have an effect on colors, and many color genes have an effect on the pattern.

Motley extends the edges of the saddles to create a ladder-like pattern. The dorsal patterning on motleys is highly variable and they can have anything from no connected saddles to all of them connected. Some will have striping which isn't caused by the stripe gene. Although the ventral checkering is also removed, this does not mean the belly has to be pure white. The wash of colors found on many different corns will also appear on motleys, as well as some black peppering. The important part of the "plain belly" is the loss of rectangular markings. One exception to this rule is the presence of intermittent checkering on sunkissed motleys. Motleys are also selecetively bred for "hurricane" patterns where the insides of the saddles are faded out. Other variations in the pattern are q-tipping and pin-striping.

Stripe is an allele at the motley locus and is recessive to motley. (Corns heterozygous for motley and stripe, correctly called "motley het stripe" corns, take on the motley phenotype.) The ventral pattern resembles that of motleys. The dorsal pattern consists of four thin saddle-colored stripes. Stripes also vary into "cubed" morphs, where squarish borderless markings on the back will appear instead of (or along with) the striping. There is still a lot of misunderstanding that this gene causes the striping in motley stripes even though this theory has been shown to be false many times. This idea persists mainly because of the use of the term "motley/stripe" which is an anti-informational term: calling something a motley/stripe raises more question than it answers. A "motley/stripe" could equally be assumed to mean 1- a snake het for motley and stripe with a motley pattern, 2- a snake het for motley and stripe with a stripey motley pattern, 3- a snake homozygous for motley with a stripey motley pattern, and different people use the term in different ways. As you can see, the term "motley/stripe" (and its cousin "striped motley") tells you absolutely nothing about the snake's pattern, and absolutely nothing about its genotype. To clear up the situation I recommend the following usage:
GenotypePatternCall it a
Homo MotleyMotleyMotley
Homo MotleyStripingPinstriped Motley
Het StripeMotleyMotley Het Stripe*
Het StripeStripingPinstriped Motley Het Stripe

*There are also claims that "motley het stripe" is technically incorrect. Why is this a problem when nobody will claim that describing a normal-looking snake het for normal and amel at the amel locus as a "normal het amel" is technically incorrect, even though it's the same situation? Because there is a false assumption that "morph name means exactly the same as homo morph name." This is just a byproduct of people being spoiled because they only had to deal with recessive mutants for such a long time. Certain abbreviations and shortcuts are always true if every mutant is recessive. It was useful back then... was! Those assumptions are now nonsensical since we are also dealing with non-recessive mutants, so it is time to throw them out instead of trying to prop them up when they don't work anymore. In real-life everyday usage, the term "motley" can refer to either the genotype or phenotype, and does not automatically mean "homozygous motley" any more than "normal" means "homozygous normal." So if a motley-looking snake is het for the stripe gene, it is correctly described as a motley het for stripe.

Terrazzo is a simple-recessive gene which causes a ventral pattern resembling that of motleys and stripes. The dorsal pattern is somewhat like an aztec stripe, where pattern tends to break up and disappear toward the tail end of the snake. It has been shown that terrazzo is not an allele to motley, and resides at its own new locus.

Tessera is a dominant gene which typically causes a full-body stripe. Some have belly checkers and others don't. It has already been combined with most other genes. There is still a lot of new information to discover about how much variation is to be expected from tesseras.

Diffusion is the main gene involved in bloodred corns. It tends to diffuse out the side pattern. In the 80's, Kathy & Bill Love originally named the bloodred morph based on its coloration. In 2004, recognizing that the bloodred morph contained a pattern gene, they suggested that the pattern be called diffused or diffusion. Many hobbyists including myself have supported this recommendation and as a result it is now possible to draw the distinction between diffused corns only expressing the on/off gene, and bloodred corns with the extra selection. Diffusion is highly variable and its effect can be anywhere from mild and almost unnoticed, to extreme where the pattern cuts off and becomes a blur at the edges of the saddles. The ventral checkering on diffused corns is also wiped out, but as with motley there may be peppering and washes of colors. This gene is sometimes considered codominant but the diffusion gene is recessive. This theory continues because other influences (often the masque gene) cause what are mistaken for "het markers." (This is another mistaken term, since if you can tell a het by looking at it, it's a codominant gene and the "marker" is simply the het phenotype.)

Pied-sided was first discovered in bloodreds and it is unknown whether this is an allele to diffusion, or if it is an independent gene that stacks its effect on top of diffusion to produce the pied-sided morph. Outcrosses are being made and should eventually provide us with clues to whether it can be separated from diffusion. Many such outcrosses are producing pied-sided results, suggesting the gene may be codominant instead of recessive. The simplest way to describe this morph is that it slows the downward pattern migration so much that the belly pattern appears on the sides of the snake.

Masque is a mild pattern gene and appears to be dominant and possibly sex-linked. It is one of the components in the production of top-end bloodred corns. Masque seems to have mild melanin-reducing, border-reducing, and pattern-stretching effects. The most obvious characteristics are found in males and consist of a stretched head pattern often producing a "skull" look, and a "white stripe" down the center of the belly where checkers do not reach the middle. Since it is easily seen in carriers, it is easily selected in bloodred projects, which has caused it to be mistaken for a side-effect of the diffusion gene, but it can be separated from the diffusion gene and acts independently once separated. Masque is almost universal in silverqueen lines as well.

Sunkissed is usually considered a color but is also worth mentioning here. The pattern effect is one of increased ground areas and/or eroded saddles. As with most patterns, it is highly variable. In the milder specimens the saddles are more rectangular, and in the extreme specimens the saddles are reduced to ovals.

Palmetto is a newly proven recessive mutation which removes all but a few specks of color.

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