Allele – either of the two paired genes which affect an inheritable trait.
Codominant – a gene that causes the homozygous form to look different than the wild-type and the heterozygous form to have traits of both.
DNA (Deoxyribonucleic Acid) – molecules bearing genetic information of all living cells. Gene. Also referred to as “unit of inheritance.”
Dominant – a gene that causes an animal to look different than the wild-type and where the homozygous form and the heterozygous form look the same as each other.
Double Heterozygous – being heterozygous for two different traits.
Gene – unit of heredity that determines the characteristics of the offspring.
Genetics – the study of heredity.
Genotype – an organism’s genetic composition. Heredity – the transmission of genetic characters from parents to offspring.
Het – an abbreviation for heterozygous.
Heterozygous – possessing two different genes for a given trait. An animal with one mutated, recessive gene still appears normal; its mutated gene can be inherited by future offspring. A codominant animal is heterozygous for the dominant form of its mutated gene, yet is different in appearance than both the wild-type and homozygous forms.
Homozygous – A state in which both genes for a specific trait are the same. When a recessive gene is it its homozygous form, it makes the animal look different from the wild-type. When a dominant gene is in its homozygous state, it causes the animal to look different from both the wild-type and the heterozygous (codominant) forms.
Locus – a gene’s position on a chromosome (plural: loci)
Mutation – an abnormal gene that under certain circumstances can cause an animal to be born with an appearance other than wild-type.
Normal – an animal with no mutated genes – “wild type” in appearance. (See wild type)
Phenotype – an animal’s external apperance, as caused by its genotype.
Possible Het. – an animal from a known breeding that has either a 50% or 66% possibility of being “heterozygous” for a mutant gene.
A 66% possible het comes from breeding 2 heterozygous animals together: 50% of the offspring are heterozygous, 25% will be homozygous, and 25% will be wild-type. Of the normal appearing animals, 66% (or roughly 2 out of 3) will actually be heterozygous for the mutated gene.
A 50% possible het comes from breeding a heterozygous animal to a wild-type animal. All of the resulting offspring will be wild-type in appearance, but 50% of them will actually be heterozygous for the mutated gene and must be bred out to determine which animals are really hets.
Recessive – a gene that affects an animal’s appearance if it’s present in the homozygous state. A heterozygous animal carrying a mutated, recessive gene looks normal.
Super – commonly used herpetocultural term for the dominant form of a co-dominant mutation. i.e. Super Pastel
Tyrosinase – an enzyme required for synthesizing melanin.
Tyrosinase-negative – an albino whose cells lack tyrosinase, producing a white and yellow/orange animal with pink eyes. A separate albino mutation from tyrosinase-positive. Also called T- .
Tyrosinase-positive – an albino not able to synthesize melanin, but capable of synthesizing tyrosinase, which results in lavender-brown skin color. Also referred to as T+ .
Examples of Recessive Traits:
Examples of Co-Dominant Traits and its Super Form:
Butter / Blue Eyed Leucistic
Lesser / Blue Eyed Leucistic
Mojave / Super Mojave
Mystic / Super Mystic
Enchi / Super Enchi
Fire / Black Eyed Leucistic
Pastel / Super Pastel
Yellowbelly / Ivory
Cinnamon / Super Cinnamon
Black Pastel / Super Black Pastel
GHI / Super GHI
Scaleless Head / Scaleless
Examples of Dominant Traits:
Co-Dominant x Normal
Pastel x Normal = ½ Pastels, and ½ Normals
Co-Dominant (Super Form) x Normal
Super Pastel x Normal = All Pastel
Co-Dominant x Co-Dominant
Pastel x Pastel = ½ Pastels, ¼ Super Pastels, and ¼ Normals
Dominant x Normal
Pinstripe x Normal = ½ Pinstripes, and ½ Normals
Dominant x Dominant
Pinstripe x Pinstripe = All Pinstripes
Recessive x Normal
Albino x Normal = All Het. Albinos
Recessive x Het. Recessive
Albino x Het. Albino = ½ Albinos, and ½ Het. Albinos
Recessive x Recessive
Albino x Albino = All Albinos
Het. Recessive x Het. Recessive
Het. Albino x Het. Albino = ½ Het. Albinos, ¼ Albinos, and ¼ Normals
Co-Dominant x Recessive
Pastel x Albino = ½ Pastels Het. Albinos, and ½ Het. Albinos