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Silver Dapple Gene
The silver or silver dapple (''Z'') gene is a dilution gene that affects the black base coat color and is associated with Multiple Congenital Ocular Abnormalities. It will typically dilute a black mane and tail to a silvery gray or flaxen color, and a black body to a chocolaty brown, sometimes with dapples."Horse coat color tests -Silver Dilution" from the Veterinary Genetics Lab It is responsible for a group of coat colors in horses called "silver dapple" in the west, or "taffy" in Australia. The most common colors in this category are '' |
Dominance Relationship
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and the second recessive. This state of having two different variants of the same gene on each chromosome is originally caused by a mutation in one of the genes, either new (''de novo'') or inherited. The terms autosomal dominant or autosomal recessive are used to describe gene variants on non-sex chromosomes ( autosomes) and their associated traits, while those on sex chromosomes (allosomes) are termed X-linked dominant, X-linked recessive or Y-linked; these have an inheritance and presentation pattern that depends on the sex of both the parent and the child (see Sex linkage). Since there is only one copy of the Y chromosome, Y-linked traits cannot be dominant or recessive. Additionally, there are other forms of dominance such as incomplete d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shetland Pony
The Shetland pony is a Scottish breed of pony originating in the Shetland Isles in the north of Scotland. It may stand up to at the withers. It has a heavy coat and short legs, is strong for its size, and is used for riding, driving, and pack purposes. History Shetland ponies originated in the Shetland Isles, located northeast of mainland Scotland. Small horses have been kept in the Shetland Isles since the Bronze Age. People who lived on the islands probably later crossed the native stock with ponies imported by Norse settlers. Shetland ponies also were probably influenced by the Celtic pony, brought to the islands by settlers between 2000 and 1000 BCE. The harsh climate and scarce food developed the ponies into extremely hardy animals. Shetland ponies were first used for pulling carts and for carrying peat, coal and other items, and ploughing land. Then, as the Industrial Revolution increased the need for coal in the mid-nineteenth century, thousands of Shetland ponie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
