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Acromicric Dysplasia
Acromicric dysplasia is an extremely rare inherited disorder characterized by abnormally short hands and feet, growth retardation and delayed bone maturation leading to short stature. Most cases have occurred randomly for no apparent reason (sporadically). However, autosomal dominant inheritance has not been ruled out. The disorder is different (but similar to) from other syndromic entities such as geleophysic dysplasia, Weill-Marchesani syndrome, and Myhre syndrome. Genetics This condition has been associated with mutations in the Fibrillin 1 ( FBN1) gene.Wang T, Yang Y, Dong Q, Zhu H, Liu Y (2020) Acromicric dysplasia with stiff skin syndrome-like severe cutaneous presentation in an 8-year-old boy with a missense FBN1 mutation: Case report and literature review. Mol Genet Genomic Med Mutations in this gene have also been associated with stiff skin syndrome, Marfan syndrome Marfan syndrome (MFS) is a multi-systemic genetic disorder that affects the connective tissue. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inherited Disorder
A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders are the most common, the term is mostly used when discussing disorders with a single genetic cause, either in a gene or chromosome. The mutation responsible can occur spontaneously before embryonic development (a ''de novo'' mutation), or it can be inherited from two parents who are carriers of a faulty gene ( autosomal recessive inheritance) or from a parent with the disorder ( autosomal dominant inheritance). When the genetic disorder is inherited from one or both parents, it is also classified as a hereditary disease. Some disorders are caused by a mutation on the X chromosome and have X-linked inheritance. Very few disorders are inherited on the Y chromosome or mitochondrial DNA (due to their size). There are well over 6,000 known g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Short Stature
Short stature refers to a height of a human which is below typical. Whether a person is considered short depends on the context. Because of the lack of preciseness, there is often disagreement about the degree of shortness that should be called ''short''. Dwarfism is the condition of being very short, often caused by a medical condition. In a medical context, short stature is typically defined as an adult height that is more than two standard deviations below a population’s mean for age and gender, which corresponds to the shortest 2.3% of individuals in that population. The median or typical adult height in developed countries is about for men and for women. Causes Shortness in children and young adults nearly always results from below-average growth in childhood, while shortness in older adults usually results from loss of height due to kyphosis of the spine or collapsed vertebrae from osteoporosis. The most common causes of short stature in childhood are constitutional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autosomal Dominant
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] |
Myhre Syndrome
Myhre syndrome is a rare genetic disorder inherited in an autosomal dominant fashion. It is caused by mutation in SMAD4 gene. Signs and symptoms The clinical presentation is variable but includes * developmental and growth delay * athletic muscular built * skeletal anomalies * joint stiffness * characteristic facial appearance * deafness * variable cognitive deficits * tracheal stenosis * aortic stenosis * pyloric stenosis The facial abnormalities include: * blepharophimosis (an abnormally narrow gap between the upper and lower eyelids) * maxillary hypoplasia (underdevelopment of the upper jaw) * prognathism (prominent lower jaw) The skeletal abnormalities include: * short stature * square body shape * broad ribs * iliac hypoplasia * brachydactyly * flattened vertebrae * thickened calvaria Congenital heart disease and undescended testes have also been reported in association with this syndrome. Genetics Myhre syndrome is due to mutations in the SMAD4 SMAD4, also called SMAD f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FBN1
Fibrillin-1 is a protein that in humans is encoded by the ''FBN1'' gene, located on chromosome 15. It is a large, extracellular matrix glycoprotein that serves as a structural component of 10-12 nm calcium-binding microfibrils. These microfibrils provide force bearing structural support in elastic and nonelastic connective tissue throughout the body. Mutations altering the protein can result in a variety of phenotypic effects differing widely in their severity, including fetal death, developmental problems, Marfan syndrome or in some cases Weill-Marchesani syndrome. ''FBN1'' gene ''FBN1'' is a 230-kb gene with 65 coding exons that encode a 2,871-amino-acid long proprotein called profibrillin which is proteolytically cleaved near its C-terminus by the enzyme furin convertase to give fibrillin-1, a member of the fibrillin family, and the 140-amino-acid long protein hormone asprosin. FBN-1 protein structure The sequence of fibrillin-1 includes 47 six-cysteine EGF-like domain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stiff Skin Syndrome
Stiff skin syndrome (also known as "Congenital fascial dystrophy") is a cutaneous condition characterized by ‘rock hard’ induration, thickening of the skin and subcutaneous tissues, limited joint mobility, and mild hypertrichosis in infancy or early childhood. Immunologic abnormalities or vascular hyperactivity are not present in patients. Not much is known about it, cause or treatment, and further investigation is required, as it has only been reported 41 times throughout history. Genetics This condition is associated with mutations in the Fibrillin 1 ( FBN1) gene. Diagnosis Differential diagnosis Other conditions associated with mutations in this gene include acromicric dysplasia, Marfan syndrome and its variant Marfanoid–progeroid–lipodystrophy syndrome, autosomal dominant Weill-Marchesani syndrome, isolated ectopia lentis, MASS phenotype, and Shprintzen-Goldberg syndrome. See also * Scleroderma * Self-healing papular mucinosis * List of cutaneous condi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marfan Syndrome
Marfan syndrome (MFS) is a multi-systemic genetic disorder that affects the connective tissue. Those with the condition tend to be tall and thin, with long arms, legs, fingers, and toes. They also typically have exceptionally flexible joints and abnormally curved spines. The most serious complications involve the heart and aorta, with an increased risk of mitral valve prolapse and aortic aneurysm. The lungs, eyes, bones, and the covering of the spinal cord are also commonly affected. The severity of the symptoms is variable. MFS is caused by a mutation in ''FBN1'', one of the genes that makes fibrillin, which results in abnormal connective tissue. It is an autosomal dominant disorder. In about 75% of cases, it is inherited from a parent with the condition, while in about 25% it is a new mutation. Diagnosis is often based on the Ghent criteria. There is no known cure for MFS. Many of those with the disorder have a normal life expectancy with proper treatment. Management of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marfanoid–progeroid–lipodystrophy Syndrome
Marfanoid–progeroid–lipodystrophy syndrome (MPL), also known as Marfan lipodystrophy syndrome (MFLS) or progeroid fibrillinopathy, is an extremely rare medical condition which manifests as a variety of symptoms including those usually associated with Marfan syndrome, an appearance resembling that seen in neonatal progeroid syndrome (NPS; also known as Wiedemann–Rautenstrauch syndrome), and severe partial lipodystrophy. It is a genetic condition that is caused by mutations in the ''FBN1'' gene, which encodes profibrillin, and affects the cleavage products of profibrillin, fibrillin-1, a fibrous structural protein, and asprosin, a glucogenic protein hormone. As of 2016, fewer than 10 cases of the condition have been reported. Lizzie Velásquez and Abby Solomon have become known publicly through the media for having the condition. In addition to severe lipodystrophy (loss of adipose tissue), individuals with MPL show a concomitant marked loss of lean tissue mass, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ectopia Lentis
Ectopia lentis is a displacement or malposition of the eye's crystalline lens from its normal location. A partial dislocation of a lens is termed lens subluxation or subluxated lens; a complete dislocation of a lens is termed lens luxation or luxated lens. Ectopia lentis in dogs and cats Although observed in humans and cats, ectopia lentis is most commonly seen in dogs. Ciliary zonules normally hold the lens in place. Abnormal development of these zonules can lead to primary ectopia lentis, usually a bilateral condition. Luxation can also be a secondary condition, caused by trauma, cataract formation (decrease in lens diameter may stretch and break the zonules), or glaucoma (enlargement of the globe stretches the zonules). Steroid administration weakens the zonules and can lead to luxation, as well. Lens luxation in cats can occur secondary to anterior uveitis (inflammation of the inside of the eye). Anterior lens luxation With anterior lens luxation, the lens pushes into the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MASS Phenotype
MASS syndrome is a medical disorder of the connective tissue similar to Marfan syndrome. MASS stands for: Mitral valve prolapse, Aortic root diameter at upper limits of normal for body size, Stretch marks of the skin, and Skeletal conditions similar to Marfan syndrome. It is caused by a mutation in the ''FBN1'' gene, which encodes fibrillin-1. Fibrillin-1 is an extracellular matrix protein that is found in microfibrils; defects in the fibrillin-1 protein cause the malfunctioning of microfibrils, which results in improper stretching of ligaments, blood vessels, and skin. Treatment options for MASS syndrome are largely determined on a case-by-case basis and generally address the symptoms as opposed to the actual disorder; furthermore, due to the similarities between these two disorders, individuals with MASS syndrome follow the same treatment plans as those with Marfan syndrome. Other possible symptoms are mitral valve prolapse, a large aortic root diameter, and myopia. The ske ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
