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Achondroplasia
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 Rhizomelia, arms and legs are short, while the torso is typically of normal length. Those affected have an average adult height of for males and for females. Other features can include an Macrocephaly, enlarged head with Skull bossing, 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 Gain-of-function, overactive. Achondroplasia results in impaired endochondral bone growth (bone growth within car ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dwarfism
Dwarfism is a condition of people and animals marked by unusually small size or short stature. In humans, it is sometimes defined as an adult height of less than , regardless of sex; the average adult height among people with dwarfism is . ''Disproportionate dwarfism'' is characterized by either Rhizomelia, short limbs or a short torso. In cases of ''proportionate dwarfism'', both the limbs and torso are unusually small. Intelligence is usually normal, and most people with it have a nearly normal life expectancy. People with dwarfism can usually bear children, although there are additional Pregnancy risks, risks to the mother and child depending upon the underlying condition. The most common and recognizable form of dwarfism in humans (comprising 70% of cases) is achondroplasia, a genetic disorder whereby the limbs are diminutive. Growth hormone deficiency is responsible for most other cases. There are many other less common causes. Treatment of the condition depends on the u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibroblast Growth Factor Receptor 3
Fibroblast growth factor receptor 3 (FGFR-3) is a protein that in humans is encoded by the ''FGFR3'' gene. FGFR3 has also been designated as CD333 (cluster of differentiation 333). The gene, which is located on chromosome 4, location p16.3, is expressed in tissues such as the cartilage, brain, intestine, and kidneys. The FGFR3 gene produces various forms of the FGFR-3 protein; the location varies depending on the isoform of FGFR-3. Since the different forms are found within different tissues the protein is responsible for multiple growth factor interactions. Gain of function mutations in FGFR3 inhibits chondrocyte proliferation and underlies achondroplasia and hypochondroplasia. Function FGFR-3 is a member of the fibroblast growth factor receptor family, where amino acid sequence is highly conserved between members and throughout evolution. FGFR family members differ from one another in their ligand affinities and tissue distribution. A full-length representative protein wou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudoachondroplasia
Pseudoachondroplasia is an inherited disorder of bone growth. It is a genetic autosomal dominant disorder. It is generally not discovered until 2–3 years of age, since growth is normal at first. Pseudoachondroplasia is usually first detected by a drop of linear growth in contrast to peers, a waddling gait or arising lower limb deformities. Pseudoachondroplasia (also known as PSACH, pseudoachondroplastic dysplasia, and pseudoachondroplastic spondyloepiphyseal dysplasia syndrome) is an osteochondrodysplasia that results in mild to severely short stature due to the inhibition of skeletal growth primarily in the limbs. Though similarities in nomenclature may cause confusion, pseudoachondroplasia should not be confused with achondroplasia, which is a clinically and genetically distinct skeletal dysplasia. Pseudoachondroplasia is caused by a heterozygous mutation in the gene encoding cartilage oligomeric matrix protein (COMP). Mutation in the COMP gene can also cause multiple epi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrocephaly
Macrocephaly is a condition in which circumference of the human head is abnormally large. It may be pathological or harmless, and can be a Heredity, familial genetic characteristic. People diagnosed with macrocephaly will receive further medical tests to determine whether the syndrome is accompanied by particular Disorder (medicine), disorders. Those with benign or familial macrocephaly are considered to have megalencephaly. Causes Many people with abnormally large heads or large skulls are healthy, but macrocephaly may be pathological. Pathologic macrocephaly may be due to megalencephaly (enlarged brain), hydrocephalus (abnormally increased cerebrospinal fluid), cranial hyperostosis (bone overgrowth), and other conditions. Pathologic macrocephaly is called "syndromic", when it is associated with any other noteworthy condition, and "nonsyndromic" otherwise. Pathologic macrocephaly may be caused by congenital anatomic abnormalities, genetic conditions, or by environmental events. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Short-limb Skeletal Dysplasia With Severe Combined Immunodeficiency
Short-limb skeletal dysplasia with severe combined immunodeficiency is an extremely rare autosomal recessive type of achondroplasia which is characterized by short stature, bowing of the long bones, and generalized metaphyseal abnormalities alongside signs of SCID such as recurrent severe infections, failure to thrive, chronic diarrhea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ..., and a notable absence of T and B lymphocytes. Around 11 cases have been described in medical literature. References Cell surface receptor deficiencies Connective tissue diseases Growth disorders Rare diseases Immunodeficiency Genetic diseases and disorders Autosomal recessive disorders {{Genetic-disorder-stub} ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lordosis
Lordosis is historically defined as an ''abnormal'' inward curvature of the lumbar spine. However, the terms ''lordosis'' and ''lordotic'' are also used to refer to the normal inward curvature of the lumbar and cervical vertebrae, cervical regions of the human vertebral column, spine. Similarly, kyphosis historically refers to ''abnormal'' convex curvature of the spine. The normal outward (convex) curvature in the thoracic and sacrum, sacral regions is also termed ''kyphosis'' or ''kyphotic''. The term comes . Lordosis in the human vertebral column, human spine makes it easier for humans to bring the bulk of their mass over the pelvis. This allows for a much more efficient walking Gait (human), gait than that of other primates, whose inflexible spines cause them to resort to an inefficient forward-leaning "bent-knee, bent-waist" gait. As such, lordosis in the human spine is considered one of the primary physiological adaptations of the human skeleton that allows for human gait ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypochondroplasia
Hypochondroplasia (HCH) is a developmental disorder caused by an autosomal dominant genetic defect in the fibroblast growth factor receptor 3 gene ('' FGFR3'') that results in a disproportionately short stature, micromeliaupdate 2013 and a head that appears large in comparison with the underdeveloped portions of the body. It is classified as short-limbed dwarfism. Signs and symptoms Individuals affected by this disorder appear normal at birth. As the infant grows, however, their arms and legs do not develop properly, and their body becomes thicker and shorter than normal. The following are characteristics consistent with this condition: * Brachydactyly * Short stature * Micromelia * Skeletal dysplasia * Abnormality of femur Cause Hypochondroplasia is inherited as an autosomal dominant trait affecting the ''FGFR3'' gene on chromosome 4p16.3. There is currently no cure for this condition. Pathophysiology This disorder results from mutations in the proximal tyrosine kinase doma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skull Bossing
Skull bossing is a descriptive term in medical physical examination indicating a protuberance of the skull, most often in the frontal bones of the forehead ("frontal bossing"). Although prominence of the skull bones may be normal, skull bossing may be associated with certain medical conditions, including nutritional, metabolic, hormonal, and hematologic disorders. Frontal bossing Frontal bossing is the development of an unusually pronounced forehead which may also be associated with a heavier than normal brow ridge. It is caused by enlargement of the frontal bone, often in conjunction with abnormal enlargement of other facial bones, skull, mandible, and bones of the hands and feet. Frontal bossing may be seen in a few rare medical syndromes such as acromegaly – a chronic medical disorder in which the anterior pituitary gland produces excess growth hormone (GH). Frontal bossing may also occur in diseases resulting in chronic anemia, where there is increased hematopoiesis and enl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizomelia
Rhizomelia refers to either a disproportion of the length of the proximal limb, such as the shortened limbs of achondroplasia, or some other disorder of the hip or shoulder. According to Stedman's medical dictionary "rhizomelic" means "relating to hip or shoulder joints", while "micromelic" means "having disproportionately short or small limbs". Genetic skeletal dysplasias or Osteochondrodysplasia frequently lead to short stature, occasionally termed dwarfism, which is classified into proportionate and disproportionate short stature. Disproportionate short stature is further classified short-limb short stature and short-trunk short stature. In turn, short-limb short stature is classified into a) Rhizomelic, b) mesomelic and c) acromelic short stature. Rhizomelic short stature refers to skeletal dysplasias where the main shortening is due to involvement of the proximal limb segments i.e. femora and humeri. Typical examples of Rhizomelic short stature are achondroplasia and pseudoacho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torso
The torso or trunk is an anatomical terminology, anatomical term for the central part, or the core (anatomy), core, of the body (biology), body of many animals (including human beings), from which the head, neck, limb (anatomy), limbs, tail and other appendages extend. The tetrapod torso — including that of a human body, human — is usually divided into the ''chest, thoracic'' segment (also known as the upper torso, where the forelimbs extend), the ''abdomen, abdominal'' segment (also known as the "mid-section" or "midriff"), and the ''pelvic'' and ''perineum, perineal'' segments (sometimes known together with the abdomen as the lower torso, where the hindlimbs extend). Anatomy Major organs In humans, most critical Organ (anatomy), organs, with the notable exception of the brain, are housed within the torso. In the upper chest, the heart and lungs are protected by the rib cage, and the abdomen contains most of the organs responsible for digestion: the stomach, which breaks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep Apnea
Sleep apnea (sleep apnoea or sleep apnœa in British English) is a sleep-related breathing disorder in which repetitive Apnea, pauses in breathing, periods of shallow breathing, or collapse of the upper airway during sleep results in poor ventilation and sleep disruption. Each pause in breathing can last for a few seconds to a few minutes and often occurs many times a night. A choking or snorting sound may occur as breathing resumes. Common symptoms include daytime sleepiness, snoring, and non restorative sleep despite adequate sleep time. Because the disorder disrupts normal sleep, those affected may experience sleepiness or feel tired during the day. It is often a chronic condition. Sleep apnea may be categorized as obstructive sleep apnea (OSA), in which breathing is interrupted by a blockage of air flow, central sleep apnea (CSA), in which regular unconscious breath simply stops, or a combination of the two. OSA is the most common form. OSA has four key contributors; these ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
