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Oculocutaneous Albinism
Oculocutaneous albinism is a form of Albinism in humans, albinism involving the human eye, eyes (''wikt:oculo-#Prefix, oculo-''), the human skin, skin (''-wikt:cutaneous#Adjective, cutaneous''), and the hair. Overall, an estimated 1 in 20,000 people worldwide are born with oculocutaneous albinism. OCA is caused by mutations in several genes that control the biosynthesis, synthesis of melanin within the melanocytes. Seven types of oculocutaneous albinism have been described, all caused by a disruption of melanin synthesis and all autosomal recessive disorders. Oculocutaneous albinism is also found in non-human animals. Types The following types of oculocutaneous albinism have been identified in humans. See also * Piebaldism * List of skin conditions * List of cutaneous conditions associated with increased risk of nonmelanoma skin cancer References External links Oculocutaneous albinism informationat RareDiseases.org NCBI Genetic Testing Registry {{DEFAULTSORT:Ocul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albinism In Humans
Albinism is a congenital condition characterized in humans by the partial or complete absence of Biological pigment, pigment in the skin, hair and eyes. Albinism is associated with a number of vision defects, such as photophobia, nystagmus, and amblyopia. Lack of skin pigmentation makes for more susceptibility to sunburn and skin cancers. In rare cases such as Chédiak–Higashi syndrome, albinism may be associated with deficiencies in the transportation of melanin granules. This also affects essential granules present in immune cells, leading to increased susceptibility to infection. Albinism results from inheritance of Dominance (genetics), recessive gene alleles and is known to affect all vertebrates, including humans. It is due to absence or defect of tyrosinase, a copper-containing enzyme involved in the production of melanin. Unlike humans, other animals have multiple Biological pigments, pigments and for these Albinism in biology, albinism is considered to be a hereditar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Point (coat Color)
A point is a small dot or the sharp tip of something. Point or points may refer to: Mathematics * Point (geometry), an entity that has a location in space or on a plane, but has no extent; more generally, an element of some abstract topological space * Point, or Element (category theory), generalizes the set-theoretic concept of an element of a set to an object of any category * Critical point (mathematics), a stationary point of a function of an arbitrary number of variables * Decimal point * Point-free geometry * Stationary point, a point in the domain of a single-valued function where the value of the function ceases to change Places * Point, Cornwall, England, a settlement in Feock parish * Point, Lewis, a peninsula in the Outer Hebrides, Scotland * Point, Texas, a city in Rains County, Texas, United States * Point, the NE tip and a ferry terminal of Lismore, Inner Hebrides, Scotland * Points, West Virginia, an unincorporated community in the United States Business an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Testing
Genetic testing, also known as DNA testing, is used to identify changes in DNA sequence or chromosome structure. Genetic testing can also include measuring the results of genetic changes, such as RNA analysis as an output of gene expression, or through biochemical analysis to measure specific protein output. In a medical setting, genetic testing can be used to diagnose or rule out suspected genetic disorders, predict risks for specific conditions, or gain information that can be used to customize medical treatments based on an individual's genetic makeup. Genetic testing can also be used to determine biological relatives, such as a child's biological parentage (genetic mother and father) through DNA paternity testing, or be used to broadly predict an individual's ancestry. Genetic testing of plants and animals can be used for similar reasons as in humans (e.g. to assess relatedness/ancestry or predict/diagnose genetic disorders), to gain information used for selective breed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is separated from Mainland Australia, Australia by the wide Torres Strait, though both landmasses lie on the same continental shelf, and were united during episodes of low sea level in the Pleistocene glaciations as the combined landmass of Sahul. Numerous smaller islands are located to the west and east. The island's name was given by Spanish explorer Yñigo Ortiz de Retez during his maritime expedition of 1545 due to the perceived resemblance of the indigenous peoples of the island to those in the Guinea (region), African region of Guinea. The eastern half of the island is the major land mass of the nation of Papua New Guinea. The western half, known as Western New Guinea, forms a part of Indonesia and is organized as the provinces of Pap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TYRP1
Tyrosinase-related protein 1, also known as TYRP1, is an intermembrane enzyme which in humans is encoded by the ''TYRP1'' gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei .... Function Tyrp1 is a melanocyte-specific gene product involved in melanin synthesis within melanosomes. Most Tyrp1 possess 5,6-dihydroxyindole-2-carboxylic acid (melanogenic intermediate) oxidase activity. The catalytic function of Tyrp1 in human melanocytes is less clear. Tyrp1 is involved in stabilizing of tyrosinase protein and modulating its catalytic activity. Tyrp1 is also involved in maintenance of melanosome structure and affects melanocyte proliferation and melanocyte cell death. Melanocytes are derived from the neural crest and migrate into the overlying epidermal ectoderm of a developing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MC1R
The melanocortin 1 receptor (MC1R), also known as melanocyte-stimulating hormone receptor (MSHR), melanin-activating peptide receptor, or melanotropin receptor, is a G protein–coupled receptor that binds to a class of pituitary peptide hormones known as the melanocortins, which include adrenocorticotropic hormone (ACTH) and the different forms of melanocyte-stimulating hormone (MSH). It is coupled to Gαs and upregulates levels of cAMP by activating adenylyl cyclase in cells expressing this receptor. It is normally expressed in skin and melanocytes, and to a lesser degree in periaqueductal gray matter, astrocytes and leukocytes. In skin cancer, MC1R is highly expressed in melanomas but not carcinomas. MC1R is one of the key proteins involved in regulating mammalian skin color and hair color. It is located on the plasma membrane of specialized cells known as melanocytes, which produce the pigment melanin through the process of melanogenesis. It controls the typ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological properties, and its behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code (its genotype) and the influence of environmental factors. Both factors may interact, further affecting the phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and again in his 1982 book '' The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as caddisfly larva cases and beaver dams ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mole (skin Marking)
Nevus () is a nonspecific medical terminology, medical term for a visible, circumscribed, chronic (medicine), chronic lesion of the skin or mucosa. The term originates from , which is Latin for "birthmark"; however, a nevus can be either congenital (present at birth) or acquired. Common terms (''mole'', ''birthmark'', ''beauty mark'', etc.) are used to describe nevi, but these terms do not distinguish specific types of nevi from one another. Classification The term ''nevus'' is applied to a number of conditions caused by Neoplasm, neoplasias and hyperplasias of melanocytes, as well as a number of pigmentation disorders, both hypermelanotic (containing increased melanin, the pigment responsible for skin color) and hypomelanotic (containing decreased melanin). Suspicious skin moles which are multi-colored or pink may be a finding in skin cancer. Increased melanin Usually acquired * Melanocytic nevus ** Melanocytic nevi can be categorized based on the location of melanocytic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freckles
Freckles are clusters of concentrated melaninized cells which are most easily visible on people with a fair complexion. Freckles do not have an increased number of the melanin-producing cells, or melanocytes, but instead have melanocytes that overproduce melanin granules ( melanosomes) changing the coloration of the outer skin cells (keratinocytes). As such, freckles are different from lentigines and moles, which are caused by accumulation of melanocytes in a small area. Freckles can appear on all types of skin tones. Of the six Fitzpatrick skin types, they are most common on skin tones 1 and 2, which usually belong to North Europeans. However, it can also be found on people all over the world. In England a historical term for freckles is summer-voys, sometimes spelt summervoise, which may be related to the German term ''Sommersprossen''. Biology The formation of freckles is caused by exposure to sunlight. The exposure to UV-B radiation activates melanocytes to increase mela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OCA2
P protein, also known as melanocyte-specific transporter protein or pink-eyed dilution protein homolog, is a protein that in humans is encoded by the oculocutaneous albinism II (''OCA2'') gene. The P protein is believed to be an integral membrane protein involved in small molecule transport, specifically of tyrosine—a precursor of melanin. Certain mutations in OCA2 result in type 2 oculocutaneous albinism. OCA2 encodes the human homologue of the mouse p (pink-eyed dilution) gene. The human OCA2 gene is located on the long arm (q) of chromosome 15, specifically from base pair 28,000,020 to base pair 28,344,457 on chromosome 15. Function OCA2 provides instructions for making the protein called P protein which is located in melanocytes which are specialized cells that produce melanin, and in the cells of the retinal pigment epithelium. Melanin is responsible for giving color to the skin, hair, and eyes. Moreover, melanin is found in the light-sensitive tissue of the retina of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WebMD
WebMD is an American corporation which publishes online news and information about human health and well-being. The WebMD website also includes information about drugs and is an important healthcare information website and the most popular consumer-oriented health site. WebMD was started in 1998 by internet entrepreneur Jeff Arnold. In early 1999, it was part of a three-way merger with Sapient Health Network (SHN) and Direct Medical Knowledge (DMK). SHN began in Portland, Oregon, in 1996 by Jim Kean, Bill Kelly, and Kris Nybakken, who worked together at a CD-ROM publishing firm, Creative Multimedia. Later, in 1999, WebMD merged with Healtheon, founded by Netscape Communications founder James H. Clark. History WebMD is best known as a health information services website, which publishes content regarding health and health care topics, including a symptom checklist, pharmacy information, drugs information, and blogs of physicians with specific topics, and provides a place t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
