I saw this article in one of my books, and I wanted to write about it. I left all the DNA-stuff behind because even that was confusing me. So I decided to only use the stuff that was about the genes, recessive and dominant. I’m sure you ever had this in biology-class. I admit that this is not my strongest point, genes, and genetics. But it was worth the try! Oh, and don’t mind my awful writing, I had trouble translating some things.
Dominant & Recessive
Genetic variation with the characteristics of the cat, like their length of the fur, is dominant if only the half of the allele is needed to make that characteristic visible.
With recessive characteristics are both sides from the allele needed to become visible. Generally, original characteristics are dominant and new different characteristics are recessive.
An allele is one of two or more forms of a gene or a genetic locus (generally a group of genes). “Allel” is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation. However, many variations at the genetic level result in little or no observable variation. – Wikipedia
In big cat populations mutations disappear automatically. But in small, isolated populations it has more influence because their chance to survive is bigger. The long-term-impact from the first members of the cat population is called “The Founder Effect”. The founders have a lot of influence on the population, it explains the genetic characteristic Polydactyl (extra toes) in new England, and the cats without tails on the island Man.
In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population. The founder effect is a special case of genetic drift, occurring when a small group in a population splinters off from the original population and forms a new one. The new colony may have less genetic variation than the original population, and through the random sampling of alleles during reproduction of subsequent generations, continue rapidly towards fixation. This consequence of inbreeding makes the colony more vulnerable to extinction. – Wikipedia
Breeds & Genetic Deviation
Breeders use the genetics to select specified characteristics. But they can also select dangerous hidden genes. That’s how genetic diseases are caused within a breed. New researches and breeding programs have to reduce the risk on genetic diseases.
Dominant, Recessive or equally strong?
A kitten receives from each parent a gene. If one of those genes gives instruction to become a tabby-fur, and the other for a black-fur, you might think that the fur of the kitten will be something in between. But it won’t! This has to do with dominant genes. If you look at the heredity of the dominant genes, you will understand that it is possible that one litter consists out of several colors and patterns.
The tabby-gene(A) is dominant compared to the non-tabby gen(a). Only if there are two copies of the recessive gene that are inherited, the kitten will have a non-tabby fur. In this example, all tabby-black combinations get a tabby fur. But if they cross breed with each other they will also have black kittens. Because both parents carry the recessive gene for black.