Punnet Squares - Is a diagram that is used to predict an outcome of a particular cross or breeding experiment. The genes of one parent are shown along the top and the genes of the other shown down the left-hand side. The 4 meeting squares is a summary of every possible outcome for that particular combination.
It should be noted that punnet squares can provide more than 4 different outcomes depending on the genetic make up of the maternal and paternal alleles.
We shall use Punnet Squares to illustrate some of the various combinations, which make up the base colours:
Standard Grey - Chin 1 - Standard Grey (aa) + Chin 2 - Standard Grey (aa)
100% of the offspring of this combination will be Standard Grey with Homozygous Recessive genes (aa).
White - Chin 1 - Standard Grey (aa) + Chin 2 - White (Aa)
50% of this chinchilla colour combination would result in Standard Grey offspring and 50% will be White - either Mosaic, Silver or Wilson White.
White - Chin 1 - White (Aa) + Chin 2 - White (Aa)
Two white chinchillas that are bred together carry a fatality gene as a White chinchilla cannot exist in the Homozygous (AA) state. This punnet square confirms this with 25% of the offspring carrying the fatality gene, which will be reabsorbed, 25% would be Standard Grey in colour and the remaining 50% would be Heterozygous White like their parents.
Heterozygous Beige - Chin 1 - Heterozygous Beige (Aa) + Chin 2 - Standard Grey (aa)
Breeding a Heterozygous Beige and a Standard Grey chinchilla together will result in 50% offspring as Heterozygous Beige and 50% Standard Grey.
Homozygous Beige - Chin 1 - Homozygous Beige (AA) + Chin 2 - Heterozygous Beige (Aa)
Combining two Beige chinchillas together - one in the Homozygous state and the other in the Heterozygous form, produces 50% Homozygous Beige and 50% Heterozygous Beige offspring.
* 100% Homozygous Beige offspring is produced if both parents are Homozygous Beige themselves.
Violet - Chin 1 - Violet Carrier (Aa) + Chin 2 - Violet Carrier (Aa)
As Violet is a recessive colour mutation it will only be exposed in the fur if bred with another Violet chinchilla either in the Homozygous state (AA) or as another 'carrier' (Aa). This combination of two Violet carriers produces 25% Pure Violet (AA), 25% Standard Grey and 50% Standard Grey - Violet Carriers (Aa).
Violet (example 2) - Chin 1 - Violet Carrier (Aa) + Chin 2 - Homozygous Violet (AA)
Combining a Violet 'carrier' with a pure Homozygous Violet produces 50% Violet offspring and 50% Standard Grey - Violet Carriers.
* 100% Violet offspring is produced if both parents are Violet in the Homozygous form.
Sapphire - Chin 1 - Homozygous Sapphire (AA) + Chin 2 - Homozygous Sapphire (AA)
Sapphire is another recessive colour mutation and if you wanted to be guaranteed to produce offspring of a recessive colour mutation in the first generation you are best to breed two Homozygous chins together. In this example, we bred two Homozygous Sapphires together and produced 100% Homozygous Sapphire offspring. All of these chinchillas would express this recessive colour mutation within their fur.
Charcoal - Chin 1 - Heterozygous Charcoal (Aa) + Chin 2 Heterozygous Charcoal (Aa)
A combination of two Charcoal carriers will produce 25% Homozygous Charcoal (AA), 25% Standard Grey and 50% Standard Grey - Charcoal Carriers.
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