Using the CalculatorEnter in one or more traits for each parents and click the calculate button. There are two ways you can enter traits:
- Typeahead (default): type the first few characters and options will display which can be selected with a click, enter or tab. Generally faster to use.
- Select: shows a popup menu of traits. Select one or more. Might be better if you don't like to type at all and/or would like to scroll through all available traits. Control-click (or command-click) to select multiple with keyboard.
Please report missing genes or other errors.
Basic Boa Constrictor Genetics
Children inherit genes from their parents that give them varied physical appearance, such as color and pattern mutations. For each gene a parent carries, it has a 50% chance of passing it down to its offspring. Thus, the offspring receives zero, one (heterozygous aka "het"), or two (i.e., a pair, called homozygous aka "super") of each of the genes based its parents genetics and chance.
Genes which are dominant produce visual effects even if only a single gene of a chromosome pair is carried. A single parent with this gene can produce this type of offspring. In true dominance, the same visual effect is achieved with either a single gene or pair of genes. When a single and pair produce different appearances, it is referred to as incomplete dominance (often called codominance in the community although these have slightly different meanings).
Other genes are recessive, and only affect visible appearance if the full pair is carried. To breed offspring with visible recessive traits, both parents must possess at least one copy (aka be "het") of this gene. Note that the calculator also includes other traits like line-bred and polygenic traits, but being less understood, these are indicated in offspring with the possible form.
|Recessive Genes||Possible Het||Het||Visual|
In reality, this is all a simplification of how genetics actually work, but this is the model that has been found useful by the reptile community. For more information, check out our article on Dominance types and our resources page.