Hi! Welcome back to the genetic series. Today I will tell you about how the red coat color is formed and I will show how Ragdoll’s red hair looks under the microscope, and at the end of the video you will find descriptions of this color in the standards of WCC affiliated organizations. Locus, i.e. areas of the chromosome in which a particular gene is located, are responsible for the formation of individual fur colors in cats. So to put it simply, the locus is such a “container” for gen. In previous episodes of the series, we talked about the container for “B” genes, which are responsible for the shape and size of eumelanin granules, i.e. black pigment and a container for “D” genes, which are responsible for the concentration of pigment in the hair. Today, we are primarily interested in the third container – into which the “o” genes fall, which are responsible for the production of pheomelanin, i.e. the red pigment. The large “O” gene is responsible for the appearance of red pigment in the hair, and the small “o” gene is responsible for the lack of red pigment in the hair. The container for these genes is located on the X chromosome and this is key information, which is why today’s hashtag for watchful is #x. This means that, in contrast to the colors discussed so far – the inheritance of this color is related to the sex of the cat. As a reminder, usually each individual has two chromosomes. For a male individual, this is XY. For a female individual this is XX. This means that female cats that have two X chromosomes also have two places for the “o” gene. Males have only one X chromosome, so only one place for the “o” gene. This is why it is enough for a male cat to inherit only one large “O” gene from any parent – to be red. And on the other hand, it is enough to inherit at least one small “o” gene so that the red pigment does not form. If a male cat draws a small “o”, it is not red, and genes from the “b” container, which is one of the variations of black pigment, are responsible for the color of his hair. It can therefore be said that the “O” gene container masks the color obtained with the “B” gene container. This means that if your cat is genetically black, chocolate or cinnamon thanks to the “B” container, then if the “O” gene container is also red no black pigment formed in the “B” container will be produced in the hair, only the red pigment formed in the “O” container. Black, chocolate or cinnamon will be present in the cat’s genes, but when we look at the cat, we will only see the color of the red. The “O” container masks the color obtained with the “B” container. However, he remains under the influence of the “D” gene container – but I will tell you about it in the next episode about cream color. Returning to the gender issue, female cats have two chromosomes, and thus two places for “o” genes. This means that they are red only if they draw two large ‘O’ genes and they are not red only if they draw two small ‘o’ genes. And what happens if it inherits one large “O” and one small “o”? They are tortie – but I will tell you about it in one of the next videos. Meanwhile, I want to show you a red pigment under a microscope. It looks like this: The rules regarding inheritance of red color are the same for cats of all breeds, so far the content of the film is universal. However, this series is primarily dedicated to Ragdoll cats, which is why I will quote the red color standards for Ragdolls later in the film. The ore color for this breed is recognized in all WCC affiliated organizations, although not all standards describe it in detail. In the FIFe standard, we will only read that this color occurs. The SACC, TICA and WCF standards for the Ragoll breed do not describe the colors in detail, so that’s all for today but I invite you next time – we will talk about cream color.