Achondrogenesis is a number of disorders that are the most severe form of congenital chondrodysplasia (malformation of bones and cartilage). These conditions are characterized by a small body, short limbs, and other skeletal abnormalities. As a result of their serious health problems, infants with achondrogenesis are usually born prematurely, are stillborn, or die shortly after birth from respiratory failure. Some infants, however, have lived for a while with intensive medical support. Researchers have described at least three forms of achondrogenesis, designated as Achondrogenesis type 1A, achondrogenesis type 1B and achondrogenesis type 2. These types are distinguished by their signs and symptoms, inheritance pattern, and genetic cause. Other types of achondrogenesis may exist, but they have not been characterized or their cause is unknown. Achondrogenesis type 1A is caused by a defect in the microtubules of the Golgi apparatus. In mice, a nonsense mutation in the thyroid hormone receptor interactor 11 gene (Trip11), which encodes the Golgi microtubule-associated protein 210 (GMAP-210), resulted in defects similar to the human disease. When their DNA was sequenced, human patients with achondrogenesis type 1A also had loss-of-function mutations in GMAP-210. GMAP-210 moves proteins from the endoplasmic reticulum to the Golgi apparatus. Because of the defect, GMAP-210 is not able to move the proteins, and they remain in the endoplasmic reticulum, which swells up. The loss of Golgi apparatus function affects some cells, such as those responsible for forming bone and cartilage, more than others. Achondrogenesis type 1B is caused by a similar mutation in SLC26A2, which encodes a sulfate transporter. Achondrogenesis, type 2 is one of several skeletal disorders caused by mutations in the COL2A1 gene. Achondrogenesis, type 2 and hypochondrogenesis (a similar skeletal disorder) together affect 1 in 40,000 to 60,000 births.

Reference
Wiki: Achondrogenesis

    Achondroplasia is a genetic disorder with an autosomal dominant pattern of inheritance whose primary feature is dwarfism. It is the most common cause of dwarfism and affects about 1 in 27,500 people. In those with the condition, the arms and legs are short, while the torso is typically of normal length. Those affected have an average adult height of 131 centimetres (4 ft 4 in) for males and 123 centimetres (4 ft) for females. Other features can include an enlarged head with prominent forehead (frontal bossing) and underdevelopment of the midface (midface hypoplasia). Complications can include sleep apnea or recurrent ear infections. Achondroplasia includes the extremely rare short-limb skeletal dysplasia with severe combined immunodeficiency. Achondroplasia is caused by a mutation in the fibroblast growth factor receptor 3 (FGFR3) gene that results in its protein being overactive. Achondroplasia results in impaired endochondral bone growth (bone growth within cartilage). The disorder has an autosomal dominant mode of inheritance, meaning only one mutated copy of the gene is required for the condition to occur. About 80% of cases occur in children of parents without the disease, and result from a new (de novo, or sporadic) mutation, which most commonly originates as a spontaneous change during spermatogenesis. The rest are inherited from a parent with the condition. The risk of a new mutation increases with the age of the father. In families with two affected parents, children who inherit both affected genes typically die before birth or in early infancy from breathing difficulties. The condition is generally diagnosed based on the clinical features but may be confirmed by genetic testing. Mutations in FGFR3 also cause achondroplasia related conditions including hypochondroplasia and SADDAN (severe achondroplasia with developmental delay and acanthosis nigricans), a rare disorder of bone growth characterized by skeletal, brain, and skin abnormalities resulting in severe short-limb skeletal dysplasia with severe combined immunodeficiency. Treatments include small molecule therapy with a C-natriuretic peptide analog (vosoritide), approved to improve growth velocity in children with achondroplasia based on results in Phase 3 human trials, although its long-term effects are unknown. Growth hormone therapy may also be used. Efforts to treat or prevent complications such as obesity, hydrocephalus, obstructive sleep apnea, middle ear infections or spinal stenosis may be required. Support groups support people with achondroplasia, including the Little People of America (LPA) and Growing Stronger. Nonprofit physician organizations also exist to disseminate information about treatment and management options, including development of patient resources.

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Wiki: Achondroplasia

    Acromesomelic dysplasia is a rare skeletal disorder that causes abnormal bone and cartilage development, leading to shortening of the forearms, lower legs, hands, feet, fingers, and toes. Five different genetic mutations have been implicated in the disorder. Treatment is individualized but is generally aimed at palliating symptoms, for example, treatment of kyphosis and lumbar hyperlordosis.

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Wiki: Acromesomelic dysplasia

    A bone inflammation disease that involves a response to irritation or injury, characterized by joint pain, swelling, stiffness located_in joint.

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DiseaseOntology: Arthritis

    Atelosteogenesis, type II is a severe disorder of cartilage and bone development. It is rare, and infants with the disorder are usually stillborn; those who survive birth die soon after.

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Wiki: Atelosteogenesis

    Osteopetrosis, literally "stone bone", also known as marble bone disease or Albers-Sch?nberg disease, is an extremely rare inherited disorder whereby the bones harden, becoming denser, in contrast to more prevalent conditions like osteoporosis, in which the bones become less dense and more brittle, or osteomalacia, in which the bones soften. Osteopetrosis can cause bones to dissolve and break. It is one of the hereditary causes of osteosclerosis. It is considered to be the prototype of osteosclerosing dysplasias. The cause of the disease is understood to be malfunctioning osteoclasts and their inability to resorb bone. Although human osteopetrosis is a heterogeneous disorder encompassing different molecular lesions and a range of clinical features, all forms share a single pathogenic nexus in the osteoclast. The exact molecular defects or location of the mutations taking place are unknown. Osteopetrosis was first described in 1903, by German radiologist Albers-Sch?nberg.

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Wiki: Autosomal recessive osteopetrosis

    Hip dysplasia is an abnormality of the hip joint where the socket portion does not fully cover the ball portion, resulting in an increased risk for joint dislocation. Hip dysplasia may occur at birth or develop in early life. Regardless, it does not typically produce symptoms in babies less than a year old. Occasionally one leg may be shorter than the other. The left hip is more often affected than the right. Complications without treatment can include arthritis, limping, and low back pain. Females are affected more often than males. Risk factors for hip dysplasia include female sex, family history, certain swaddling practices, and breech presentation whether an infant is delivered vaginally or by cesarean section. If one identical twin is affected, there is a 40% risk the other will also be affected. Screening all babies for the condition by physical examination is recommended. Ultrasonography may also be useful. Many of those with mild instability resolve without specific treatment. In more significant cases, if detected early, bracing may be all that is required. In cases that are detected later, surgery and casting may be needed. About 7.5% of hip replacements are done to treat problems which have arisen from hip dysplasia. About 1 in 1,000 babies have hip dysplasia. Hip instability of meaningful importance occurs in one to two percent of babies born at term. Females are affected more often than males. Hip dysplasia was described at least as early as the 300s BC by Hippocrates.

Reference
Wiki: Beukes hip dysplasia

    A bone tumor is an abnormal growth of tissue in bone, traditionally classified as noncancerous (benign) or cancerous (malignant). Cancerous bone tumors usually originate from a cancer in another part of the body such as from lung, breast, thyroid, kidney and prostate. There may be a lump, pain, or neurological signs from pressure. A bone tumor might present with a pathologic fracture. Other symptoms may include fatigue, fever, weight loss, anemia and nausea. Sometimes there are no symptoms and the tumour is found when investigating another problem. Diagnosis is generally by X-ray and other radiological tests such as CT scan, MRI, PET scan and bone scintigraphy. Blood tests might include a complete blood count, inflammatory markers, serum electrophoresis, PSA, kidney function and liver function. Urine may be tested for Bence Jones protein. For confirmation of diagnosis, a biopsy for histological evaluation might be required. The most common bone tumor is a non-ossifying fibroma. Average five-year survival in the United States after being diagnosed with bone and joint cancer is 67%. The earliest known bone tumor was an osteosarcoma in a foot bone discovered in South Africa, between 1.6 and 1.8 million years ago.

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Wiki: Bone cancer

    An osteosarcoma (OS) or osteogenic sarcoma (OGS) (or simply bone cancer) is a cancerous tumor in a bone. Specifically, it is an aggressive malignant neoplasm that arises from primitive transformed cells of mesenchymal origin (and thus a sarcoma) and that exhibits osteoblastic differentiation and produces malignant osteoid. Osteosarcoma is the most common histological form of primary bone sarcoma. It is most prevalent in teenagers and young adults.

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Wiki: Bone osteosarcoma

    Boomerang dysplasia is a lethal form of osteochondrodysplasia known for a characteristic congenital feature in which bones of the arms and legs are malformed into the shape of a boomerang. Death usually occurs in early infancy due to complications arising from overwhelming systemic bone malformations. Osteochondrodysplasias are skeletal disorders that cause malformations of both bone and cartilage.

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Wiki: Boomerang dysplasia

    Brachydactyly (Greek ¦Â¦Ñ¦Á¦Ö?? 'short' plus ¦Ä?¦Ê¦Ó¦Ô¦Ë¦Ï? 'finger') is a medical term which literally means 'short finger'. The shortness is relative to the length of other long bones and other parts of the body. Brachydactyly is an inherited, dominant trait. It most often occurs as an isolated dysmelia, but can also occur with other anomalies as part of many congenital syndromes. Brachydactyly may also be a signal that one is at risk for congenital heart disease due to the association between congenital heart disease and Carpenter syndrome and the link between Carpenter syndrome and brachydactyly. Nomograms for normal values of finger length as a ratio to other body measurements have been published. In clinical genetics, the most commonly used index of digit length is the dimensionless ratio of the length of the third (middle) finger to the hand length. Both are expressed in the same units (centimeters, for example) and are measured in an open hand from the fingertip to the principal creases where the finger joins the palm and where the palm joins the wrist.

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Wiki: Brachydactyly

    Bruck syndrome is characterized as the combination of arthrogryposis multiplex congenita and osteogenesis imperfecta. Both diseases are uncommon, but concurrence is extremely rare which makes Bruck syndrome very difficult to research. Bruck syndrome is thought to be an atypical variant of osteogenesis imperfecta most resembling type III, if not its own disease. Multiple gene mutations associated with osteogenesis imperfecta are not seen in Bruck syndrome. Many affected individuals are within the same family, and pedigree data supports that the disease is acquired through autosomal recessive inheritance. Bruck syndrome has features of congenital contractures, bone fragility, recurring bone fractures, flexion joint and limb deformities, pterygia, short body height, and progressive kyphoscoliosis. Individuals encounter restricted mobility and pulmonary function. A reduction in bone mineral content and larger hydroxyapatite crystals are also detectable Joint contractures are primarily bilateral and symmetrical, and most prone to ankles. Bruck syndrome has no effect on intelligence, vision, or hearing.

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Wiki: Bruck syndrome

    Calvarial doughnut lesions-bone fragility syndrome, also known as familial calvarial doughnut lesions, is a rare autosomal dominant genetic disorder characterized by mild to moderate fragility of the bones accompanied with calvarial doughnut lesions.

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Wiki: Calvarial doughnut lesions with bone fragility and spondylometaphyseal dysplasia

    Campomelic dysplasia (CMD) is a genetic disorder characterized by bowing of the long bones and many other skeletal and extraskeletal features. It can be lethal in the neonatal period due to respiratory insufficiency, but the severity of the disease is variable, and a significant proportion of patients survive into adulthood. The name is derived from the Greek roots campo (or campto), meaning bent, and melia, meaning limb. An unusual aspect of the disease is that up to two-thirds of affected 46,XY genotypic males display a range of disorders of sexual development (DSD) and genital ambiguities or may even develop as normal phenotypic females as in complete 46 XY sex reversal. An atypical form of the disease with absence of bowed limbs is called, prosaically, acampomelic campomelic dysplasia (ACD) and is found in about 10% of patients, particularly those surviving the neonatal period.

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Wiki: Campomelic dysplasia

    Camurati¨CEngelmann disease (CED) is a very rare autosomal dominant genetic disorder that causes characteristic anomalies in the skeleton. It is also known as progressive diaphyseal dysplasia. It is a form of dysplasia. Patients typically have heavily thickened bones, especially along the shafts of the long bones (called diaphyseal dysplasia). The skull bones may be thickened so that the passages through the skull that carry nerves and blood vessels become narrowed, possibly leading to sensory deficits, blindness, or deafness. This disease often appears in childhood and is considered to be inherited, however many patients have no previous history of CED within their family. The disease is slowly progressive and, while there is no cure, there is treatment. It is named for M. Camurati and G. Engelmann.

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Wiki: Camurati-Engelmann disease

    A bone disease that is characterized by the Pierre Robin anomaly, which comprises cleft palate, glossoptosis, and micrognathia, and a unique form of bilateral hyperphalangy in which there is an accessory bone inserted between the second metacarpal and its corresponding proximal phalanx, resulting in radial deviation of the index finger and that has_material_basis_in homozygous or compound heterozygous mutation in the TGDS gene on chromosome 13q32.

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DiseaseOntology: Catel Manzke syndrome

    Chondrosarcoma is a bone sarcoma, a primary cancer composed of cells derived from transformed cells that produce cartilage. A chondrosarcoma is a member of a category of tumors of bone and soft tissue known as sarcomas. About 30% of bone sarcomas are chondrosarcomas. It is resistant to chemotherapy and radiotherapy. Unlike other primary bone sarcomas that mainly affect children and adolescents, a chondrosarcoma can present at any age. It more often affects the axial skeleton than the appendicular skeleton.

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Wiki: Chondrosarcoma

    Cleidocranial dysostosis (CCD), also called cleidocranial dysplasia, is a birth defect that mostly affects the bones and teeth. The collarbones are typically either poorly developed or absent, which allows the shoulders to be brought close together. The front of the skull often does not close until later, and those affected are often shorter than average. Other symptoms may include a prominent forehead, wide set eyes, abnormal teeth, and a flat nose. Symptoms vary among people; however, intelligence is typically unaffected. The condition is either inherited or occurs as a new mutation. It is inherited in an autosomal dominant manner. It is due to a defect in the RUNX2 gene which is involved in bone formation. Diagnosis is suspected based on symptoms and X-rays with confirmation by genetic testing. Other conditions that can produce similar symptoms include mandibuloacral dysplasia, pyknodysostosis, osteogenesis imperfecta, and Hajdu-Cheney syndrome. Treatment includes supportive measures such as a device to protect the skull and dental care. Surgery may be performed to fix certain bone abnormalities. Life expectancy is generally normal. It affects about one per million people. Males and females are equally commonly affected. Modern descriptions of the condition date to at least 1896. The term is from cleido meaning collarbone, cranial from the Greek ¦Ê¦Ñ¦Á¦Í?¦Ï meaning skull, and dysostosis meaning formation of abnormal bone.

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Wiki: Cleidocranial dysplasia

    An osteochondrodysplasia characterized by short stature, joint laxity, scoliosis, and advanced carpal ossification with a delta phalanx.

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DiseaseOntology: Desbuquois dysplasia

    Hardcastle syndrome is a rare genetic disorder on chromosome 9 at 9p22-p21.[2] It affects the long bones.[3][4] There is a high risk for histiocytoma.[5]

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Wiki: Diaphyseal medullary stenosis-bone malignancy syndrome

    Ewing sarcoma is a type of pediatric cancer that forms in bone or soft tissue. Symptoms may include swelling and pain at the site of the tumor, fever, and a bone fracture. The most common areas where it begins are the legs, pelvis, and chest wall. In about 25% of cases, the cancer has already spread to other parts of the body at the time of diagnosis. Complications may include a pleural effusion or paraplegia. It is a type of small round cell sarcoma. The cause of Ewing sarcoma is unknown, most cases appearing to occur randomly. Though not strongly associated with known hereditary cancer syndromes, accumulating evidence suggests a strong inherited risk factor, identifying a genetic component having multiple chromosome loci associated with Ewing sarcoma susceptibility. Sometimes Ewing sarcoma is associated with a germline mutation. The underlying mechanism often involves a genetic change known as a reciprocal translocation. Diagnosis is based on biopsy of the tumor. Treatment often includes chemotherapy, radiation therapy, surgery, and stem cell transplant. Targeted therapy and immunotherapy are being studied. Five-year survival is about 70%. A number of factors, however, affect this estimate. In 1920, James Ewing discerned that these tumors are a distinct type of cancer. It affects approximately one in a million people per year in the United States. Ewing sarcoma occurs most often in teenagers and young adults and represents 2% of childhood cancers. Caucasians are affected more often than African Americans or Asians, while males are affected more often than females.

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Wiki: Ewing sarcoma

    Fibrosarcoma (fibroblastic sarcoma) is a malignant mesenchymal tumour derived from fibrous connective tissue and characterized by the presence of immature proliferating fibroblasts or undifferentiated anaplastic spindle cells in a storiform pattern. Fibrosarcomas mainly arise in people between the ages of 25 and 79. It originates in fibrous tissues of the bone and invades long or flat bones such as the femur, tibia, and mandible. It also involves the periosteum and overlying muscle.

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Wiki: Fibrosarcoma

    Cherubism is a rare genetic disorder that causes prominence in the lower portion in the face. The name is derived from the temporary chubby-cheeked resemblance to putti, the chubby-faced infants featured in Renaissance paintings, which were often mistakenly described as cherubs.

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Wiki: Fibrous dysplasia of jaw

    Giant-cell tumor of the bone (GCTOB), is a relatively uncommon tumor of the bone. It is characterized by the presence of multinucleated giant cells (osteoclast-like cells). Malignancy in giant-cell tumor is uncommon and occurs in about 2% of all cases. However, if malignant degeneration does occur, it is likely to metastasize to the lungs. Giant-cell tumors are normally benign, with unpredictable behavior. It is a heterogeneous tumor composed of three different cell populations. The giant-cell tumour stromal cells (GCTSC) constitute the neoplastic cells, which are from an osteoblastic origin and are classified based on expression of osteoblast cell markers such as alkaline phosphatase and osteocalcin. In contrast, the mononuclear histiocytic cells (MNHC) and multinucleated giant cell (MNGC) fractions are secondarily recruited and comprise the non-neoplastic cell population. They are derived from an osteoclast-monocyte lineage determined primarily by expression of CD68, a marker for monocytic precursor cells. In most patients, the tumors are slow to develop, but may recur locally in as many as 50% of cases.

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Wiki: Giant cell tumor of bone

    Kenny-Caffey syndrome type 2 (KCS2) is an extremely rare autosomal dominant genetic condition characterized by dwarfism, hypermetropia, microphthalmia, and skeletal abnormalities.[1] This subtype of Kenny-Caffey syndrome is caused by a heterozygous mutation in the FAM111A gene (615292) on chromosome 11q12.[2]

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Wiki: Gracile bone dysplasia

    Cant¨² syndrome is a rare condition characterized by hypertrichosis, osteochondrodysplasia, and cardiomegaly.[6][5] Less than 50 cases have been described in the literature; they are associated with a mutation in the ABCC9-gene that codes for the ABCC9-protein.[5]

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Wiki: Hypertrichotic osteochondrodysplasia

    A syndrome that is characterized by growth retardation with proportionate short stature, cortical thickening and medullary stenosis of the long bones, delayed anterior fontanelle closure, hypocalcemia due to congenital hypoparathyroidism and facial dysmorphism, including prominent forehead, microphthalmia, and micrognathia.

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DiseaseOntology: Kenny-Caffey syndrome

    An osteosclerosis that has_material_basis_in a mutation of the LEMD3 gene which results_in a hyperdense bony cortex.

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DiseaseOntology: Melorheostosis

    Microcephalic osteodysplastic primordial dwarfism type II (MOPD II) is a form of primordial dwarfism associated with brain and skeletal abnormalities. It was characterized in 1982. MOPD II is listed as a rare disease by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This indicates that MOPD (or a subtype of MOPD) affects less than 200,000 people in the US population. It is associated with the protein pericentrin (PCNT). Intelligence is reported by usually within low-normal or mild intellectual disability range. Some have average levels of intelligence, but may masked by specific learning disability.

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Wiki: Microcephalic osteodysplastic primordial dwarfism

    A bone developmental disease characterized by tall stature, scoliosis and macrodactyly of the great toes that has_material_basis_in heterozygous mutation in the NPR2 gene on chromosome 9p13.

Reference
DiseaseOntology: Miura type epiphyseal chondrodysplasia

    An osteochondrodysplasia that has_material_basis_in defective cartilage mineralization into bone which results in irregular ossification centers of the located in hip or located in knee. The disease has symptom fatigue, has symptom joint pain.

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DiseaseOntology: Multiple epiphyseal dysplasia

    An arthritis that has_material_basis_in worn out cartilage located_in joint.

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DiseaseOntology: Osteoarthritis

    Osteogenesis imperfecta (IPA: ; OI), colloquially known as brittle bone disease, is a group of genetic disorders that all result in bones that break easily.:?85? The range of symptoms¡ªon the skeleton as well as on the body's other organs¡ªmay be mild to severe.:?1512? Symptoms found in various types of OI include whites of the eye (sclerae) that are blue instead, short stature, loose joints, hearing loss, breathing problems and problems with the teeth (dentinogenesis imperfecta). Potentially life-threatening complications, all of which become more common in more severe OI, include: tearing (dissection) of the major arteries, such as the aorta;:?333? pulmonary valve insufficiency secondary to distortion of the ribcage;:?335¨C341? and basilar invagination.:?106¨C107? The underlying mechanism is usually a problem with connective tissue due to a lack of, or poorly formed, type I collagen.:?1513? In more than 90% of cases, OI occurs due to mutations in the COL1A1 or COL1A2 genes. These mutations may be hereditary in an autosomal dominant manner but may also occur spontaneously (de novo). There are four clinically defined types: type I, the least severe; type IV, moderately severe; type III, severe and progressively deforming; and type II, perinatally lethal. As of September 2021, 19 different genes are known to cause the 21 documented genetically defined types of OI, many of which are extremely rare and have only been documented in a few individuals. Diagnosis is often based on symptoms and may be confirmed by collagen biopsy or DNA sequencing. Although there is no cure, most cases of OI do not have a major effect on life expectancy,:?461? death during childhood from it is rare, and many adults with OI can achieve a significant degree of autonomy despite disability. Maintaining a healthy lifestyle by exercising, eating a balanced diet sufficient in vitamin D and calcium, and avoiding smoking can help prevent fractures. Genetic counseling may be sought by those with OI to prevent their children from inheriting the disorder from them.:?101? Treatment may include acute care of broken bones, pain medication, physical therapy, mobility aids such as leg braces and wheelchairs, vitamin D supplementation, and, especially in childhood, rodding surgery. Rodding is an implantation of metal intramedullary rods along the long bones (such as the femur) in an attempt to strengthen them. Medical research also supports the use of medications of the bisphosphonate class, such as pamidronate, to increase bone density. Bisphosphonates are especially effective in children, however it is unclear if they either increase quality of life or decrease the rate of fracture incidence. OI affects only about one in 15,000 to 20,000 people, making it a rare genetic disease. Outcomes depend on the genetic cause of the disorder (its type). Type I (the least severe) is the most common, with other types comprising a minority of cases. Moderate-to-severe OI primarily affects mobility; if rodding surgery is performed during childhood, some of those with more severe types of OI may gain the ability to walk. The condition has been described since ancient history. The Latinate term osteogenesis imperfecta was coined by Dutch anatomist Willem Vrolik in 1849; translated literally, it means "imperfect bone formation".:?683?

Reference
Wiki: Osteogenesis imperfecta

    An osteosarcoma (OS) or osteogenic sarcoma (OGS) (or simply bone cancer) is a cancerous tumor in a bone. Specifically, it is an aggressive malignant neoplasm that arises from primitive transformed cells of mesenchymal origin (and thus a sarcoma) and that exhibits osteoblastic differentiation and produces malignant osteoid.[1]

Reference
Wiki: Osteogenic sarcoma/osteosarcoma

    Osteootohepatoenteric syndrome (OOHE) is characterized by a variable combination of bone fragility, hearing loss, cholestasis, and congenital diarrhea. Some patients also display mild developmental delay and intellectual disability (Esteve et al., 2018).

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OMIM: Osteootohepatoenteric syndrome

    Osteopenia, known as "low bone mass" or "low bone density", is a condition in which bone mineral density is low. Because their bones are weaker, people with osteopenia may have a higher risk of fractures, and some people may go on to develop osteoporosis. In 2010, 43 million older adults in the US had osteopenia. Unlike osteoporosis, osteopenia does not usually cause symptoms, and losing bone density in itself does not cause pain. There is no single cause for osteopenia, although there are several risk factors, including modifiable (behavioral, including dietary and use of certain drugs) and non-modifiable (for instance, loss of bone mass with age). For people with risk factors, screening via a DXA scanner may help to detect the development and progression of low bone density. Prevention of low bone density may begin early in life and includes a healthy diet and weight-bearing exercise, as well as avoidance of tobacco and alcohol. The treatment of osteopenia is controversial: non-pharmaceutical treatment involves preserving existing bone mass via healthy behaviors (dietary modification, weight-bearing exercise, avoidance or cessation of smoking or heavy alcohol use). Pharmaceutical treatment for osteopenia, including bisphosphonates and other medications, may be considered in certain cases but is not without risks. Overall, treatment decisions should be guided by considering each patient's constellation of risk factors for fractures.

Reference
Wiki: Osteopenia

    Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to more porous bone, and consequent increase in fracture risk. It is the most common reason for a broken bone among the elderly. Bones that commonly break include the vertebrae in the spine, the bones of the forearm, the wrist, and the hip. Until a broken bone occurs there are typically no symptoms. Bones may weaken to such a degree that a break may occur with minor stress or spontaneously. After the broken bone heals, the person may have chronic pain and a decreased ability to carry out normal activities. Osteoporosis may be due to lower-than-normal maximum bone mass and greater-than-normal bone loss. Bone loss increases after the menopause due to lower levels of estrogen, and after "andropause" due to lower levels of testosterone. Osteoporosis may also occur due to a number of diseases or treatments, including alcoholism, anorexia, hyperthyroidism, kidney disease, and surgical removal of the ovaries. Certain medications increase the rate of bone loss, including some antiseizure medications, chemotherapy, proton pump inhibitors, selective serotonin reuptake inhibitors, and glucocorticosteroids. Smoking and getting an inadequate amount of exercise are also risk factors. Osteoporosis is defined as a bone density of 2.5 standard deviations below that of a young adult. This is typically measured by dual-energy X-ray absorptiometry (DXA or DEXA). Prevention of osteoporosis includes a proper diet during childhood, hormone replacement therapy for menopausal women, and efforts to avoid medications that increase the rate of bone loss. Efforts to prevent broken bones in those with osteoporosis include a good diet, exercise, and fall prevention. Lifestyle changes such as stopping smoking and not drinking alcohol may help. Bisphosphonate medications are useful to decrease future broken bones in those with previous broken bones due to osteoporosis. In those with osteoporosis but no previous broken bones, they are less effective. They do not appear to affect the risk of death. Osteoporosis becomes more common with age. About 15% of Caucasians in their 50s and 70% of those over 80 are affected. It is more common in women than men. In the developed world, depending on the method of diagnosis, 2% to 8% of males and 9% to 38% of females are affected. Rates of disease in the developing world are unclear. About 22 million women and 5.5 million men in the European Union had osteoporosis in 2010. In the United States in 2010, about 8 million women and between 1 and 2 million men had osteoporosis. White and Asian people are at greater risk. The word "osteoporosis" is from the Greek terms for "porous bones".

Reference
Wiki: Osteopetrosis

    A bone resorption disease characterized by decreased density of normally mineralized bone which results_in the thinning of bone tissue and decreased mechanical strength.

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DiseaseOntology: Osteoporosis

    A syndrome characterized by congenital or infancy-onset blindness, very low bone mass, decreased trabecular bone volume, severe juvenile-onset osteoporosis and spontaneous fractures, pseudoglioma, microphthalmia that has_material_basis_in homozygous or compound heterozygous mutation in the LRP5 gene on chromosome 11q13.

Reference
DiseaseOntology: Osteoporosis-pseudoglioma syndrome

    A bone sarcoma that is located_in bone that has_material_basis_in cells of mesenchymal origin. It usually involves bones and less frequently extraosseous sites. It often involves the long bones (particularly distal femur, proximal tibia, and proximal humerus).

Reference
DiseaseOntology: Osteosarcoma

    Paget's disease of bone (commonly known as Paget's disease or, historically, osteitis deformans) is a condition involving cellular remodeling and deformity of one or more bones. The affected bones show signs of dysregulated bone remodeling at the microscopic level, specifically excessive bone breakdown and subsequent disorganized new bone formation.[1] These structural changes cause the bone to weaken, which may result in deformity, pain, fracture or arthritis of associated joints.[1]

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Wiki: Paget disease of bone

    A syndrome that is characterized by ankylosis of the proximal interphalangeal joints, carpal and tarsal bone fusion, and conductive deafness.

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DiseaseOntology: proximal symphalangism

    Pseudo-Hurler polydystrophy, also referred to as mucolipidosis III (ML III), is a lysosomal storage disease closely related to I-cell disease (ML II).[2] This disorder is called Pseudo-Hurler because it resembles a mild form of Hurler syndrome, one of the mucopolysaccharide (MPS) diseases.

Reference
Wiki: Pseudo-hurler polydystrophy

    An osteochondrodysplasia that has_material_basis_in a mutation in the CTSK gene which results_in dwarfism, brittle bones, osteopetrosis, shortening of the distal phalanges.

Reference
DiseaseOntology: Pycnodysostosis

    Osteogenesis imperfecta, colloquially known as brittle bone disease, is a group of genetic disorders that all result in bones that break easily.[1]:?85?[9] The range of symptoms¡ªon the skeleton as well as on the body's other organs¡ªmay be mild to severe.[5]:?1512? Symptoms found in various types of OI include whites of the eye (sclerae) that are blue instead, short stature, loose joints, hearing loss, breathing problems[10] and problems with the teeth (dentinogenesis imperfecta).[5] Potentially life-threatening complications, all of which become more common in more severe OI, include: tearing (dissection) of the major arteries, such as the aorta;[1]:?333?[11] pulmonary valve insufficiency secondary to distortion of the ribcage;[1]:?335¨C341?[12] and basilar invagination.

Reference
Wiki: Recessive metabolic bone disorder

    Robinow syndrome is an extremely rare genetic disorder characterized by short-limbed dwarfism, abnormalities in the head, face, and external genitalia, as well as vertebral segmentation. The disorder was first described in 1969 by human geneticist Meinhard Robinow, along with physicians Frederic N. Silverman and Hugo D. Smith, in the American Journal of Diseases of Children. By 2002, over 100 cases had been documented and introduced into medical literature. Two forms of the disorder exist, dominant and recessive, of which the former is more common. Patients with the dominant version often suffer moderately from the aforementioned symptoms. Recessive cases, on the other hand, are usually more physically marked, and individuals may exhibit more skeletal abnormalities. The recessive form is particularly frequent in Turkey. However, this can likely be explained by a common ancestor, as these patients' families can be traced to a single town in Eastern Turkey. Clusters of the autosomal recessive form have also been documented in Oman and Czechoslovakia. The syndrome is also known as Robinow-Silverman-Smith syndrome, Robinow dwarfism, fetal face, fetal face syndrome, fetal facies syndrome, acral dysostosis with facial and genital abnormalities, or mesomelic dwarfism-small genitalia syndrome. The recessive form was previously known as Covesdem syndrome.

Reference
Wiki: Robinow syndrome

    A bone development disease characterized by early developmental delay primarily involving speech, distinct facial features, short stature, brachydactyly, clubfoot deformities, cataracts, and microcephaly that has_material_basis_in heterozygous mutation in the COG4 gene on chromosome 16q22.1.

Reference
DiseaseOntology: Saul-Wilson syndrome

    Osteopetrosis, literally "stone bone", also known as marble bone disease or Albers-Sch?nberg disease, is an extremely rare inherited disorder whereby the bones harden, becoming denser, in contrast to more prevalent conditions like osteoporosis, in which the bones become less dense and more brittle, or osteomalacia, in which the bones soften. Osteopetrosis can cause bones to dissolve and break. It is one of the hereditary causes of osteosclerosis. It is considered to be the prototype of osteosclerosing dysplasias. The cause of the disease is understood to be malfunctioning osteoclasts and their inability to resorb bone. Although human osteopetrosis is a heterogeneous disorder encompassing different molecular lesions and a range of clinical features, all forms share a single pathogenic nexus in the osteoclast. The exact molecular defects or location of the mutations taking place are unknown. Osteopetrosis was first described in 1903, by German radiologist Albers-Sch?nberg.

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Wiki: Severe osteopetrosis

    Short rib¨Cpolydactyly syndrome is a family of four closely related dysplasias: I ¨C "Saldino-Noonan type" II ¨C "Majewski type" III ¨C "Verma-Naumoff type" (associated with DYNC2H1) IV ¨C "Beemer-Langer type"

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Wiki: Short-rib polydactyly syndrome

    A bone development disease that is characterized by postnatal progressive vertebral fusions frequently manifesting as block vertebrae, contributing to an undersized trunk and a disproportionate short stature, scoliosis, lordosis, carpal and tarsal synostosis, with club feet and a mild facial dysmorphism, and that has_material_basis_in autosomal recessive inheritance of homozygous or compound heterozygous mutation in the filamin B (FLNB) gene on chromosome 3p14.3.

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DiseaseOntology: Spondylocarpotarsal synostosis syndrome

    Stuve-Wiedemann syndrome is an autosomal recessive disorder characterized by bowing of the long bones and other skeletal anomalies, episodic hyperthermia, respiratory distress, and feeding difficulties usually resulting in early death (Dagoneau et al., 2004).

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OMIM: Stuve-wiedemann syndrome

    A syndactyly characterized by an increased number of digits; often a result of a mutation in the HOXD13 gene.

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DiseaseOntology: Synpolydactyly

    Usher syndrome, also known as Hallgren syndrome, Usher¨CHallgren syndrome, retinitis pigmentosa¨Cdysacusis syndrome or dystrophia retinae dysacusis syndrome, is a rare genetic disorder caused by a mutation in any one of at least 11 genes resulting in a combination of hearing loss and visual impairment. It is the most common cause of deafblindness and is at present incurable. Usher syndrome is classed into three subtypes (I, II and III) according to the genes responsible and the onset of deafness. All three subtypes are caused by mutations in genes involved in the function of the inner ear and retina. These mutations are inherited in an autosomal recessive pattern. The occurrence of Usher syndrome varies across the world and across the different syndrome types, with rates as high as 1 in 12,500 in Germany to as low as 1 in 28,000 in Norway. Type I is most common in Ashkenazi Jewish and Acadian populations, and type III is rarely found outside Ashkenazi Jewish and Finnish populations. Usher syndrome is named after Scottish ophthalmologist Charles Usher, who examined the pathology and transmission of the syndrome in 1914.

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Wiki: Three M syndrome

    A chondrodysplasia punctata that is characterized by maxillary hypoplasia, stippled chondrodystrophy, flat nasal tip and short columella, and that has_material_basis_in a mutation in the ARSE gene on chromosome Xp22.

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DiseaseOntology: X-linked chondrodysplasia punctata 1