Here is a series of very useful charts showing various aspects of the effect of the presence of the white spotting gene including theories on how the gene works to create varying amounts of white fur. The charts come from Sarah Hartwell’s messybeast.com website with her permission. Sarah is the graphic artist. Talented lady.
The images on this page are thumbnails. This means that if you click on them you are taken to a large image with readable text! It is vital therefore that visitors click on the images if they are to benefit from them. If you are into cat coats, these charts will be interesting and useful. You can return to this page by clicking the browser’s back button.
The white spotting gene (also known as the piebald gene) causes cats to have variable amounts of white fur on a range of cat coats from solid colored coats, tabby cats to tortoiseshell coats. When the coat is solid colored, and the white spotting gene results in their being white fur as well, the coat is described as solid-and-white. Tortoiseshell-and-white is called ‘calico’ in the USA. Where there is lots of white fur with inverted triangular shaped solid colored fur around the ears the coat is the Van pattern and so on.
In general, where there is one copy of the piebald gene the cat will have a white coat anywhere between 0% and 50% of the total area of the coat. If there are two copies of the gene the amount of white fur will be between 50% to 100% of the total area.
Low grade white spotting means there is less that 40% white fur while high grade white spotting means the coat is more than 60% white.
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