Genetic mutation in the context of "Insertion (genetics)"

In botany, a sport or bud sport, traditionally called lusus, is a part of a plant that shows morphological differences from the rest of the plant. Sports may differ by foliage shape or color, flowers, fruit, or branch structure. The cause is generally thought to be chance genetic mutations in a single cell. Sports may also arise from stable changes in gene expression due to epigenetic modifications, including histone modification, DNA methylation, chromatin remodeling and RNA silencing. If the clonal descendants of a modified cell eventually form a meristem that gives rise to new plant parts, those may be of a new phenotype. Often only part of the meristem cells are affected, resulting in genetic chimerism in such sports.

Hemolytic–uremic syndrome (HUS) is a syndrome characterized by low red blood cells, acute kidney injury (previously called acute renal failure), and low platelets. Initial symptoms typically include bloody diarrhea, fever, vomiting, and weakness. Kidney problems and low platelets then occur as the diarrhea progresses. Children are more commonly affected, but most children recover without permanent damage to their health, although some children may have serious and sometimes life-threatening complications. Adults, especially the elderly, may show a more complicated presentation. Complications may include neurological problems and heart failure.

Most cases occur after infectious diarrhea due to a specific type of E. coli called O157:H7. Other causes include S. pneumoniae, Shigella, Salmonella, and certain medications. The underlying mechanism typically involves the production of Shiga toxin by the bacteria. Atypical hemolytic uremic syndrome (aHUS) is often due to a genetic mutation and presents differently. However, both can lead to widespread inflammation and multiple blood clots in small blood vessels, a condition known as thrombotic microangiopathy.

Malignant hyperthermia (MH) is a type of severe reaction that occurs in response to particular medications used during general anesthesia, among those who are susceptible. Symptoms include muscle rigidity, fever, and a fast heart rate. Complications can include muscle breakdown and high blood potassium. Most people who are susceptible to MH are generally unaffected when not exposed to triggering agents.

Exposure to triggering agents (certain volatile anesthetic agents or succinylcholine) can lead to the development of MH in those who are susceptible. Susceptibility can occur due to at least six genetic mutations, with the most common one being of the RYR1 gene. These genetic variations are often inherited in an autosomal dominant manner. The condition may also occur as a new mutation or be associated with a number of inherited muscle diseases, such as central core disease.

Neurofibromatosis (NF) refers to a group of three distinct genetic conditions in which tumors grow in the nervous system. The tumors are non-cancerous (benign) and often involve the skin or surrounding bone. Although symptoms are often mild, each condition presents differently. Neurofibromatosis type I (NF1) is typically characterized by café au lait spots (light-brown flat patches of skin), neurofibromas (small bumps in or under the skin), scoliosis (side-way curvature of the back), and headaches. Neurofibromatosis type II (NF2), on the other hand, may present with early-onset hearing loss, cataracts, tinnitus, difficulty walking or maintaining balance, and muscle atrophy. The third type is called schwannomatosis and often presents in early adulthood with widespread pain, numbness, or tingling due to nerve compression.

The cause is a genetic mutation in certain oncogenes. These can be inherited, or in about half of cases spontaneously occur during early development. Different mutations result in the three types of NF. Neurofibromatosis arise from the supporting cells of the nervous system rather than the neurons themselves. In NF1, the tumors are neurofibromas (tumors of the peripheral nerves), while in NF2 and schwannomatosis tumors of Schwann cells are more common. Diagnosis is typically based on symptoms, examination, medical imaging, and biopsy. Genetic testing may rarely be done to support the diagnosis.

Mutation breeding, sometimes referred to as "variation breeding", is the process of exposing seeds to chemicals, radiation, or enzymes in order to generate mutants with desirable traits to be bred with other cultivars. Plants created using mutagenesis are sometimes called mutagenic plants or mutagenic seeds.

From 1930 to 2014 more than 3200 mutagenic plant varieties were released that have been derived either as direct mutants (70%) or from their progeny (30%). Crop plants account for 75% of released mutagenic species with the remaining 25% ornamentals or decorative plants. However, although the FAO/IAEA reported in 2014 that over 1,000 mutant varieties of major staple crops were being grown worldwide, it is unclear how many of these varieties are currently used in agriculture or horticulture around the world, as these seeds are not always identified or labeled as having a mutagenic provenance.