Here is where we attempt to give you a simple overview of a complex subject - Genetics! The idea being to help you answer the all important question "what will I get if I cross x with y?"

Firstly are tables categorising the most popular Leopard Gecko and Royal Python morphs and below that tables showing in pictoral form the outcomes of different pairings. This is a very basic guide but we hope you will be able to take it a stage further based on the information below. At the bottom of the page is a short glossary of terms. Just hover your mouse over terms in bold to see an explanation - good luck!!

Royal Pythons

RECESSIVE

CO-DOMINANT

DOMINANT

  • Albino
  • Caramel Albino
  • Axanthic
  • Clown
  • Piebald
  • Ghost/Hypo
  • Genetic Stripe
  • Pastel
  • Mojave
  • Yellow Belly
  • Woma
  • Red Axanthic
  • Lesser Platinum
  • Butter
  • Black Pastel
  • Cinnamon
  • Fire
  • Calico
  • Phantom
  • Spotnose
  • Spider
  • Pinstripe
  • Granite
  •  Leopard Geckos 

    RECESSIVE

    CO-DOMINANT

    DOMINANT

  • Bell Albino
  • Tremper Albino
  • Blizzard
  • Murphy Patternless
  • Reverse Stripe
  • Eclipse
  • Mack Snow
  • Giant
  •  

  • Enigma
  • TUG Snow
  • It should be noted that there are a number of 'Line Bred' traits which are only passed from generation to generation through selectively breeding for that trait. Such traits can be colour or pattern traits as for example, the tangerine colour or carrot tail traits in Leopard Gecko's.

    Please find below breeding outcomes of crossing the various traits identified above, where % outcomes are given the % figure represents the % chance each animal has of being Het:

    RECESSIVE
    Heterozygous x Normal = All normal offspring 50% 'het'

    =

    Het

    Normal

    50% het

    50% het

    50% het

    50% het

    Heterozygous x Heterozygous = 75% normal offspring 66% 'het' and 25% Homozygous (visual)
    =

    Het Albino

    Het Albino

    66% het Albino

    66% het Albino

    66% het Albino

    Albino

    Homozygous x Normal = All normal offspring 100% het

    =

    Albino

    Normal

    100% het Albino

    100% het Albino

    100% het Albino

    100% het Albino

    Homozygous x Heterozygous = 50% Homozygous, 50% heterozygous
    =

    Albino

    100% het Albino

    100% het Albino

    100% het Albino

    Albino

    Albino

    Homozygous x Homozygous = 100% Homozygous
    =

    Albino

    Albino

    Albino

    Albino

    Albino

    Albino

     

     

    CO_DOMINANT
    Co-Dominant x Normal = 50% Normal, 50% Co-Dominant

    =

    Co-Dom

    Normal

    Co-Dom

    Co-Dom

    Normal

    Normal

    Co-Dominant x Co-Dominant = 50% Co-Dominant, 25% Homozygous (super form), 25% Normal
    =

    Co-Dom

    Co-Dom

    Co-Dom

    Co-Dom

    'Super' co-dom

    Normal

    Homozygous (super) x Normal = 100% Co-Dominant
    =

    Homozygous

    Normal

    Co-Dom

    Co-Dom

    Co-Dom

    Co-Dom

    Homozygous x Co-Dominant = 50% Homozygous, 50% Co-Dominant
    =

    Homozygous

    Co-Dom

    Homozygous

    Homozygous

    Co-Dom

    Co-Dom

    Homozygous x Homozygous = 100% Homozygous
    =

    Homozygous

    Homozygous

    Homozygous

    Homozygous

    Homozygous

    Homozygous

     

     

    DOMINANT
    Heterozygous x Normal = 50% Normal, 50% Heterozygous

    =

    Heterozygous

    Normal

    Heterozygous

    Heterozygous

    Normal

    Normal

    Heterozygous x Heterozygous = 25% Homozygous, 50% Heterozygous, 25% Normal
    =

    Heterozygous

    Heterozygous

    Homozygous

    Heterozygous

    Heterozygous

    Normal

    Homozygous x Normal = 100% Heterozygous
    =

    Homozygous

    Normal

    Heterozygous

    Heterozygous

    Heterozygous

    Heterozygous

    Homozygous x Heterozygous = 50% Homozygous, 50% Heterozygous
    =

    Homozygous

    Heterozygous

    Homozygous

    Homozygous

    Heterozygous

    Heterozygous

    Homozygous x Homozygous = 100% Homozygous
    =

    Homozygous

    Homozygous

    Homozygous

    Homozygous

    Homozygous

    Homozygous

     

    IMPORTANT TERMS

    Morph: this is effectively the name given to a non-wild type (or 'normal') trait in any species. Traits can be recessive, co-dominant, Dominant or Line-Bred (see below). Traits can be described as colour or pattern mutations or both. Such traits can be found naturally occurring in the wild.

    Designer Morphs: this term describes a morph created in captivity and will comprise two or more traits. Due to the rare occurance of morphs in the wild it is highly unlikely (although not impossible) to find a designer morph from wild caught stock. To be recognised as a new designer morph it must be bred in successive generations to prove its traits are genetically inheritable and to determine the nature of the trait.

    Homozygous: Homo means 'the same' and describes an animal that visually displays a trait (its phenotype) because it has two of the same genes for that trait.

    Heterozygous: Hetero means 'different'. When one parent is homozygous and the other is normal only one gene for the trait will be passed to the offspring and it will be described as being heterozygous (or het for short) for that trait because it has two different genes.

    Recessive: recessive animals require two genes of the same trait for it to display it visually. Animals that only carry one gene for a recessive trait will not visually display that trait and are commonly referred to as 'Het' or Heterozygous (Hetero meaning different).

    Co-Dominant: Traits that are described as being co-dominant are basically traits that create visual morphs when animals only have one gene for that trait. When two of the same co-dominant morphs mate a 'super form' (also called Homozygous) is created when offspring carry both genes.

    Dominant:  Dominant traits act in a similar way to co-dominant's. However, no super form is produced when two Dominant animals mate. Wild type animals are all Dominant as a wild type to any other animal will always produce some wild type offspring. Because there is no 'super' form it is impossible to tell visually whether a Dominant morph carries one or two dominant genes. This can only be determined by crossing it with a normal. In the illustrations given here we refer to a dominant morph with one dominant gene as 'heterozygous.

    When considering what breeding outcomes to expect from pairing two morphs or designer morphs you will now appreciate the importance of knowing the individual traits within each.