Coat colouring and genetic make-up
At Banksia Park Puppies, we get a lot of questions about a puppy’s colouring, relating to the colour of it’s parents. These are questions like ‘why is my puppy’s coat gold when both of it’s parents are black?’ or ‘my puppy is golden but it’s parents are red, how can this be the case?’.
I would have to go into significant scientific gene detail to completely answer these questions! But I also would like to address the question, and give you enough detail so that you can understand why a puppy’s coat is random rather than a certainty based on it’s parents.
Every puppy has DNA. This DNA is made up of a whole lot of different ‘points’. Each of these has two parts that make this up, and these can be ‘dominant’ and/or ‘recessive’. When mum and dad breed, each parent passes on one of their DNA to make up the DNA of the puppy. The gene passed on is picked at random. Each of the puppies (even within the same litter) will therefore be made up of a random set of DNA from mum, and a random set of DNA from dad (the figures below will help you understand this!).
Black or Liver
We’ll talk first about how a dog can be black or liver (for the sake of making this the basics, we’ll show liver as brown). This depends on the ‘B’ part of the DNA.
‘B’ is dominant over ‘b’.
So depending on the genetic makeup, if black mum and black dad both have a recessive ‘b’ gene (i.e. they are Bb), the puppies actually have a possibility of being liver (or another colour other than black) as they could get the ‘b’ gene from mum and dad, making then ‘bb’.
Recessive red adds an additional complexity, to make this simpler, we will only use the two recessive red genes ‘E’ and ‘e’.
E – this basically means that whatever their colour as determined by other genes (e.g. B) will occur.
e – The dog cant produce the black colour, it will produce a red/tan colour instead.
Combining the Black and Recessive Red Genes
So putting B and E together, a puppy with the following make up will have the below colour.
BBEE – black
BBEe – black (red/tan carrier)
BBee – red/tan with a black nose
BbEE – black (liver carrier)
BbEe – black (liver and red/tan carrier)
Bbee – red/tan with a black nose (liver carrier)
bbEE – liver
bbEe – liver (red/tan carrier)
bbee – red/tan with a brown (liver) nose
Here is one of the more complex examples of ‘B’ and ‘E’ together, and it shows the possibility of the colours of their puppies, and the different resulting genes.
Duplicating genes haven’t been shown in the first example, so this doesn’t show the ‘chance’.
Figure below shows the ‘chance’ of a puppy being a certain colour with duplicating genes shown.
NOTE: Just a note that this blog article doesn’t take into account many the other genes i.e. whether white patching will occur or the intensity of the colouring to create red/tan/yellow. It is put together as a simple description to show customers that puppy may not always be the same colour as mum and/or dad.