Yellow Base

What it looks like

Yellow is its own gene, not part of the Black/Red slot. It sits on top of whatever the base is: Yellow on Black reads as Olive, Yellow on Red as Orange, and Yellow alone as Yellow.

A clean, bright yellow is just Yellow. A yellow with a melanin blend (buckskin, cream, tan) points to Phantom.

This page shows Yellow Base drawn from its genes. For the written reference, inheritance tables and breeder notes, see the crested gecko morph guide on ReptiDex.

Side by side

• 

  Yellow alone

  Open in the builder
• 

  Yellow on Black (Olive)

  Open in the builder
• 

  Yellow on Red (Orange)

  Open in the builder

With other genes

• Phantom on Yellow is Cream

  Two copies of Phantom blend melanin into the yellow: cream to buckskin.

  

  

In depth

Produces yellow/light base coloration. Naturally hypo-melanistic. Dominant or co-dominant expression. Creates Creamsicle (y + optional H/TANG) and C2/Cream Squared (y + H) combo morphs. Yellow-based animals with melanin blending indicate Phantom trait.

How to spot it

Yellow Base animals show yellow/light coloration. Clean yellow (no melanin blending) = Hypo absence. Yellow with melanin = Phantom.

Where it came from

Yellow Base was identified as a distinct base color allele through selective breeding.

How it is inherited

Dominant: one copy shows.

Written as y+ and y

Yellow Base is naturally hypo-melanistic. Simple dominant inheritance. Source: Foundation Genetics Part 1.

Beside other genes

• Yellow Base and Hypo strengthen each other

  Hypo + Yellow Base creates C2/Cream Squared (fading to unicolor white cream). Enhancement of hypo effect.

Morphs it takes part in

• Blondeeasy to breed

  Light yellow coloration with yellow dorsal pattern. Clean appearance without dark melanin blending.

  Needs Yellow Base, Hypo.

• Brindlequinadvanced

  Tri-color brindle pattern with yellow, white, and dark bands/patches. Tiger breaks Harlequin concentration into brindle stripes.

  Needs Yellow Base, White Pattern, Harlequin, Pinstripe, Tiger.

• C2difficult

  Unicolor white cream color. Paper white expression possible with proper hypo stacking. Clean appearance with minimal to no dark pigmentation. Reduced pigment visible under tail base and around kneecaps.

  Needs Yellow Base, Hypo.

• Citruseasy to breed

  Bright citrus-orange to yellow-orange body coloration. More saturated than standard Tangerine. Yellow Base amplifies the orange intensity of the Tangerine background.

  Needs Yellow Base, Tangerine.

• Creamtakes some work

  Cream to buckskin base coloration. Phantom reduces melanin uniformly across the body, blending the base toward pale cream or warm tan depending on expression level. Pattern visibility is reduced. Reduced pigmentation visible under tail base and around kneecaps.

  Needs Yellow Base, Phantom.

• Creamsicletakes some work

  Cream to orange coloration. Warm tones from Yellow Base lightened by Hypo. Optional Tangerine shifts toward peach.

  Needs Yellow Base, Hypo.

• Oliveeasy to breed

  Olive to greenish-yellow base coloration. Yellow Base pigment expressed against Black Base melanin produces characteristic olive and khaki-green tones. Most pronounced when fired down. Fired-up animals shift toward brighter yellow. Depth varies based on relative copy number of each allele.

  Needs Yellow Base, Black Base.

• Orangetakes some work

  Orange to orange-red base coloration. Warmer and more saturated than Yellow Base alone. Intensity varies with expression of both alleles. Most vivid when fired up. Distinct from Red Base: orange tones rather than deep red or burgundy.

  Needs Yellow Base, Red Base.