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Structural Variation In The Human Genome
Structural variation in the human genome is operationally defined as genomic alterations, varying between individuals, that involve DNA segments larger than 1 kilo base (kb), and could be either microscopic or submicroscopic. This definition distinguishes them from smaller variants that are less than 1 kb in size such as short deletions, insertions, and single nucleotide variants. Humans have an incredibly complex and intricate genome that has been shaped and modified over time by evolution. About 99.9% of the DNA-sequence in the human genome is conserved between individuals from all over the world, but some variation does exist. Single nucleotide polymorphisms (SNPs) are considered to be the largest contributor to genetic variation in humans since they are so abundant and easily detectable. It is estimated that there are at least 10 million SNPs within the human population but there are also many other types of genetic variants and they occur at dramatically different scal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Variation
Genomic structural variation is the variation in structure of an organism's chromosome. It consists of many kinds of variation in the genome of one species, and usually includes microscopic and submicroscopic types, such as deletions, duplications, copy-number variants, insertions, inversions and translocations. Originally, a structure variation affects a sequence length about 1kb to 3Mb, which is larger than SNPs and smaller than chromosome abnormality (though the definitions have some overlap). However, the operational range of structural variants has widened to include events > 50bp. The definition of structural variation does not imply anything about frequency or phenotypical effects. Many structural variants are associated with genetic diseases, however many are not. Recent research about SVs indicates that SVs are more difficult to detect than SNPs. Approximately 13% of the human genome is defined as structurally variant in the normal population, and there are at least 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosome Structure
Eukaryotic chromosome structure refers to the levels of packaging from raw DNA molecules to the chromosomal structures seen during metaphase in mitosis or meiosis. Chromosomes contain long strands of DNA containing genetic information. Compared to prokaryotic chromosomes, eukaryotic chromosomes are much larger in size and are linear chromosomes. Eukaryotic chromosomes are also stored in the cell nucleus, while chromosomes of prokaryotic cells are not stored in a nucleus. Eukaryotic chromosomes require a higher level of packaging to condense the DNA molecules into the cell nucleus because of the larger amount of DNA. This level of packaging includes the wrapping of DNA around proteins called histones in order to form condensed nucleosomes. History The double helix was discovered in 1953 by James Watson and Francis Crick. Other researchers made very important, but unconnected findings about the composition of DNA. Ultimately it was Watson and Crick who put all of these findings toget ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AIDS
Human immunodeficiency virus infection and acquired immunodeficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV), a retrovirus. Following initial infection an individual may not notice any symptoms, or may experience a brief period of influenza-like illness. Typically, this is followed by a prolonged incubation period with no symptoms. If the infection progresses, it interferes more with the immune system, increasing the risk of developing common infections such as tuberculosis, as well as other opportunistic infections, and tumors which are rare in people who have normal immune function. These late symptoms of infection are referred to as acquired immunodeficiency syndrome (AIDS). This stage is often also associated with unintended weight loss. HIV is spread primarily by unprotected sex (including anal and vaginal sex), contaminated blood transfusions, hypodermic needles, and from mother to child duri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CCL3L1
Chemokine (C-C motif) ligand 3-like 1, also known as CCL3L1, is a protein which in humans is encoded by the ''CCL3L1'' gene. Function This gene is one of several chemokine genes clustered on the q-arm of chromosome 17. Chemokines are a family of secreted proteins involved in immunoregulatory and inflammatory processes. Specifically, chemokines attract lymphocytes to sites of infection or damage. This protein binds to several chemokine receptors including chemokine binding protein 2 ( CCBP2 or D6) and chemokine (C-C motif) receptor 5 (CCR5). CCR5 is a co-receptor for HIV, and binding of CCL3L1 to CCR5 inhibits HIV entry. Furthermore, the binding causes the receptor to be taken inside the cell by endocytosis, to eventually be reprocessed and re-expressed. Gene organization The human genome reference assembly contains two full copies of the gene (CCL3L1 and CCL3L3) and an additional partial duplication, which is thought to result in a pseudogene, designated CCL3L2. This r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hereditary Neuropathy With Liability To Pressure Palsies
Hereditary neuropathy with liability to pressure palsy (HNPP) is a peripheral neuropathy, a condition that affects the nerves.update 2014 Pressure on the nerves can cause tingling sensations, numbness, pain, weakness, muscle atrophy and even paralysis of the affected area. In normal individuals, these symptoms disappear quickly, but in sufferers of HNPP even a short period of pressure can cause the symptoms to occur. Palsies can last from minutes or days to weeks or even months. HNPP is caused by a mutation in the gene ''PMP22'', which makes peripheral myelin protein 22. This protein has a role in the maintenance of the myelin sheath that insulates nerves, resulting in insufficient conductivity in the nerves. HNPP is part of the group of hereditary motor and sensory neuropathy (HMSN) disorders and is linked to Charcot–Marie–Tooth disease (CMT). Signs and symptoms Symptoms and symptom onset vary; some individuals are diagnosed in childhood, others in adulthood, some report mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogenic
In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term ''pathogen'' came into use in the 1880s. Typically, the term ''pathogen'' is used to describe an ''infectious'' microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus. Small animals, such as helminths and insects, can also cause or transmit disease. However, these animals are usually referred to as parasites rather than pathogens. The scientific study of microscopic organisms, including microscopic pathogenic organisms, is called microbiology, while parasitology refers to the scientific study of parasites and the organisms that host them. There are several pathways through which pathogens can invade a host. The principal pathways have different episodic time frames, but soil has the longest or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Variation Mechanism
A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as biological organisms, minerals and chemicals. Abstract structures include data structures in computer science and musical form. Types of structure include a hierarchy (a cascade of one-to-many relationships), a network featuring many-to-many links, or a lattice featuring connections between components that are neighbors in space. Load-bearing Buildings, aircraft, skeletons, anthills, beaver dams, bridges and salt domes are all examples of load-bearing structures. The results of construction are divided into buildings and non-building structures, and make up the infrastructure of a human society. Built structures are broadly divided by their varying design approaches and standards, into categories including building str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
