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Agouti Coloration Genetics
The agouti gene, the Agouti-signaling protein (ASIP) is responsible for variations in color in many species. ''Agouti'' works with ''extension'' to regulate the color of melanin which is produced in hairs. The agouti protein causes red to yellow pheomelanin to be produced, while the competing molecule α-MSH signals production of brown to black eumelanin. In wildtype mice, alternating cycles of agouti and α-MSH production cause agouti coloration. Each hair has bands of yellow which grew during agouti production, and black which grew during α-MSH production. Wildtype mice also have light-colored bellies. The hairs there are a creamy color the whole length because the agouti protein was produced the whole time the hairs were growing. In mice and other species, loss of function mutations generally cause a darker color, while gain of function mutations cause a yellower coat. Mice As of 1979, there were 17 known alleles of agouti in mice. *Lethal yellow ''Ay'' causes yellow color ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Champion Dales Pony
A champion (from the late Latin ''campio'') is the victor in a challenge, contest or competition. There can be a territorial pyramid of championships, e.g. local, regional / provincial, state, national, continental and world championships, and even further (artificial) divisions at one or more of these levels, as in association football. Their champions can be accordingly styled, e.g. national champion, world champion. Meaning In certain disciplines, there are specific titles for champions, either descriptive, as the baspehlivan in Turkish oil wrestling, yokozuna in Japanese sumo wrestling; or copied from social hierarchies, such as the ''koning'' and ''keizer'' ('king' and 'emperor') in traditional archery competitions (not just national, also at lower levels) in the Low Countries. * In a broader sense, nearly any sort of competition can be considered a championship, and the winner of it a champion. Thus, there are championships for many non-sporting competitions such as s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bay Horse
Bay is a hair coat color of horses, characterized by a reddish-brown or brown body color with a black point coloration on the mane, tail, ear edges, and lower legs. Bay is one of the most common coat colors in many horse breeds. The black areas of a bay horse's hair coat are called "black points", and without them, a horse is not a bay horse. Black points may sometimes be covered by white markings; however such markings do not alter a horse's classification as "bay". Bay horses have dark skin – except under white markings, where the skin is pink. Genetically, bay occurs when a horse carries both the Agouti gene and a black base coat. While the basic genetics that create bay coloring are fairly simple, the genes themselves and the mechanisms that cause shade variations within the bay family are quite complex and, at times, disputed. The genetics of dark shades of bay are still under study. The genetic mechanism that produces seal brown has yet to be isolated. Sooty genet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chestnut (coat)
Chestnut is a hair coat color of horses consisting of a reddish-to-brown coat with a mane and tail the same or lighter in color than the coat. Chestnut is characterized by the absolute absence of true black hairs. It is one of the most common horse coat colors, seen in almost every breed of horse. Chestnut is a very common coat color but the wide range of shades can cause confusion. The lightest chestnuts may be mistaken for palominos, while the darkest shades can be so dark they appear black. Chestnuts have dark brown eyes and black skin, and typically are some shade of red or reddish brown. The mane, tail, and legs may be lighter or darker than the body coat, but unlike the bay they are never truly black. Like any other color of horse, chestnuts may have pink skin with white hair where there are white markings, and if such white markings include one or both eyes, the eyes may be blue. Chestnut foals may be born with pinkish skin, which darkens shortly afterwards. Chestnu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black (horse)
Black is a hair coat color of horses in which the entire hair coat is black. Black is a relatively uncommon coat color, and it is not uncommon to mistake dark chestnuts or bays for black. True black horses have dark brown eyes, black skin, and wholly black hair coats without any areas of permanently reddish or brownish hair. They may have pink skin beneath any white markings under the areas of white hair, and if such white markings include one or both eyes, the eyes may be blue. Many black horses "sun bleach" with exposure to the elements and sweat, and therefore their coats may lose some of their rich black character and may even resemble bay or seal brown, though examination of the color of hair around the eyes, muzzle and genitals often will determine color. Black horses that do not sun bleach are called "non-fading" blacks. Some breeds of horses, such as the Friesian horse, Murgese and Ariegeois (or Merens), are almost exclusively black. Black is also common in the Fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recessive
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] |
Bay (horse)
Bay is a hair coat color of horses, characterized by a reddish-brown or brown body color with a black point coloration on the mane, tail, ear edges, and lower legs. Bay is one of the most common coat colors in many horse breeds. The black areas of a bay horse's hair coat are called "black points", and without them, a horse is not a bay horse. Black points may sometimes be covered by white markings; however such markings do not alter a horse's classification as "bay". Bay horses have dark skin – except under white markings, where the skin is pink. Genetically, bay occurs when a horse carries both the Agouti gene and a black base coat. While the basic genetics that create bay coloring are fairly simple, the genes themselves and the mechanisms that cause shade variations within the bay family are quite complex and, at times, disputed. The genetics of dark shades of bay are still under study. The genetic mechanism that produces seal brown has yet to be isolated. Sooty genet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allele
An allele (, ; ; modern formation from Greek ἄλλος ''állos'', "other") is a variation of the same sequence of nucleotides at the same place on a long DNA molecule, as described in leading textbooks on genetics and evolution. ::"The chromosomal or genomic location of a gene or any other genetic element is called a locus (plural: loci) and alternative DNA sequences at a locus are called alleles." The simplest alleles are single nucleotide polymorphisms (SNP). but they can also be insertions and deletions of up to several thousand base pairs. Popular definitions of 'allele' typically refer only to different alleles within genes. For example, the ABO blood grouping is controlled by the ABO gene, which has six common alleles (variants). In population genetics, nearly every living human's phenotype for the ABO gene is some combination of just these six alleles. Most alleles observed result in little or no change in the function of the gene product it codes for. However, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wildtype
The wild type (WT) is the phenotype of the typical form of a species as it occurs in nature. Originally, the wild type was conceptualized as a product of the standard "normal" allele at a locus, in contrast to that produced by a non-standard, "mutant" allele. "Mutant" alleles can vary to a great extent, and even become the wild type if a genetic shift occurs within the population. Continued advancements in genetic mapping technologies have created a better understanding of how mutations occur and interact with other genes to alter phenotype. It is now appreciated that most or all gene loci exist in a variety of allelic forms, which vary in frequency throughout the geographic range of a species, and that a uniform wild type does not exist. In general, however, the most prevalent allele – i.e., the one with the highest gene frequency – is the one deemed wild type. The concept of wild type is useful in some experimental organisms such as fruit flies ''Drosophila melanogaster'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frameshift
Ribosomal frameshifting, also known as translational frameshifting or translational recoding, is a biological phenomenon that occurs during translation that results in the production of multiple, unique proteins from a single mRNA. The process can be programmed by the nucleotide sequence of the mRNA and is sometimes affected by the secondary, 3-dimensional mRNA structure. It has been described mainly in viruses (especially retroviruses), retrotransposons and bacterial insertion elements, and also in some cellular genes. Process overview Proteins are translated by reading tri-nucleotides on the mRNA strand, also known as codons, from one end of the mRNA to the other (from the 5' to the 3' end) starting with the amino acid methionine as the start (initiation) codon AUG. Each codon is translated into a single amino acid. The code itself is considered degenerate, meaning that a particular amino acid can be specified by more than one codons. However, a shift of any number of nucleo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
