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Clinodactyly
Clinodactyly is a medical term describing the curvature of a digit (a finger or toe) in the plane of the palm, most commonly the fifth finger (the "little finger") towards the adjacent fourth finger (the "ring finger"). It is a fairly common isolated anomaly which often goes unnoticed, but also occurs in combination with other abnormalities in certain genetic syndromes. The term is from the Ancient Greek κλίνειν ' 'to bend' and δάκτυλος ' 'digit'. Genetics Clinodactyly is an autosomal dominant trait that has variable expressiveness and incomplete penetrance. Clinodactyly can be passed through inheritance and presents as either an isolated anomaly or a component manifestation of a genetic syndrome. Many syndromes are associated with clinodactyly, including those listed below. But the phenotype, by itself, is not a sensitive or specific diagnostic test for these syndromes (it is present in up to 18% of the normal population). * Down syndrome * Turner syndrome * Aa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camptodactyly
Camptodactyly is a medical condition that causes one or more fingers or toes to be permanently bent. It involves fixed flexion deformity of the proximal interphalangeal joints. Camptodactyly can be caused by a genetic disorder. In that case, it is an autosomal dominant trait that is known for its incomplete genetic expressivity. This means that when a person has the genes for it, the condition may appear in both hands, one, or neither. A linkage scan proposed that the chromosomal locus of camptodactyly was 3q11.2-q13.12. Causes The specific cause of camptodactyly remains unknown, but there are a few deficiencies that lead to the condition. A deficient lumbrical muscle controlling the flexion of the fingers, and abnormalities of the flexor and extensor tendons. A number of congenital syndromes may also cause camptodactyly: * Jacobsen syndrome * Beals syndrome * Blau syndrome * Freeman–Sheldon syndrome * Cerebrohepatorenal syndrome * Weaver syndrome * Christian syndrome 1 * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camptodactyly
Camptodactyly is a medical condition that causes one or more fingers or toes to be permanently bent. It involves fixed flexion deformity of the proximal interphalangeal joints. Camptodactyly can be caused by a genetic disorder. In that case, it is an autosomal dominant trait that is known for its incomplete genetic expressivity. This means that when a person has the genes for it, the condition may appear in both hands, one, or neither. A linkage scan proposed that the chromosomal locus of camptodactyly was 3q11.2-q13.12. Causes The specific cause of camptodactyly remains unknown, but there are a few deficiencies that lead to the condition. A deficient lumbrical muscle controlling the flexion of the fingers, and abnormalities of the flexor and extensor tendons. A number of congenital syndromes may also cause camptodactyly: * Jacobsen syndrome * Beals syndrome * Blau syndrome * Freeman–Sheldon syndrome * Cerebrohepatorenal syndrome * Weaver syndrome * Christian syndrome 1 * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OSLAM Syndrome
OSLAM syndrome is a rare autosomal dominant hereditary disorder. Its name is an initialism of " osteosarcoma, limb anomalies, and erythroid macrocytosis with megaloblastic marrow syndrome". OSLAM syndrome was recognised and described by Mulvilhill ' as a syndrome that increases susceptibility to tumours and is characterised by an impaired regulation of bone and marrow development.Weber G.F. (2007.) ''Molecular Mechanisms of Cancer'', Springer, pg. 558. Individuals with OSLAM syndrome have an elevated risk of bone cancer, limb abnormalities, and enlarged red blood cells. Signs and symptoms Clinical presentation is consistent with: * Bone cancer * Curved fifth fingers (clinodactyly) with brachymesophalangy (shortened phalanges of the toes and/or fingers (digits)) * Absence of one digital ray of the foot (a digit and corresponding metacarpal or metatarsal bone) * Bilateral radioulnar synostosis Radioulnar synostosis is a rare condition where there is an abnormal connection between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Down Syndrome
Down syndrome or Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is usually associated with physical growth delays, mild to moderate intellectual disability, and characteristic facial features. The average IQ of a young adult with Down syndrome is 50, equivalent to the mental ability of an eight- or nine-year-old child, but this can vary widely. The parents of the affected individual are usually genetically normal. The probability increases from less than 0.1% in 20-year-old mothers to 3% in those of age 45. The extra chromosome is believed to occur by chance, with no known behavioral activity or environmental factor that changes the probability. Down syndrome can be identified during pregnancy by prenatal screening followed by diagnostic testing or after birth by direct observation and genetic testing. Since the introduction of screening, Down syndrome pregnancies are often abor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver–Russell Syndrome
Silver–Russell syndrome (SRS), also called Silver–Russell dwarfism, is a rare congenital growth disorder. In the United States it is usually referred to as Russell–Silver syndrome (RSS), and Silver–Russell syndrome elsewhere. It is one of 200 types of dwarfism and one of five types of primordial dwarfism. Silver–Russell syndrome occurs in approximately one out of every 50,000 to 100,000 births. Males and females seem to be affected with equal frequency. Signs and symptoms Although confirmation of a specific genetic marker is in a significant number of individuals, there are no tests to clearly determine if this is what a person has. As a syndrome, a diagnosis is typically given for children upon confirmation of the presence of several symptoms listed below. Symptoms are intrauterine growth restriction (IUGR) combined with some of the following: * Often small for gestational age (SGA) at birth (birth weight less than 2.8 kg) * Feeding problems: the baby is unintere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XXYY Syndrome
XXYY syndrome is a sex chromosome anomaly in which males have 2 extra chromosomes, one X and one Y chromosome. Human cells usually contain two sex chromosomes, one from the mother and one from the father. Usually, females have two X chromosomes (XX) and males have one X and one Y chromosome (XY). The appearance of at least one Y chromosome with a properly functioning SRY gene makes a male. Therefore, humans with XXYY are genotypically male. Males with XXYY syndrome have 48 chromosomes instead of the typical 46. This is why XXYY syndrome is sometimes written as 48, XXYY syndrome or 48, XXYY. It affects an estimated one in every 18,000–40,000 male births. Presentation Some signs and symptoms of this condition include: Cause 48,XXYY syndrome is a condition related to the X and Y chromosomes (the sex chromosomes). People normally have 46 chromosomes in each cell. Two of the 46 chromosomes, known as X and Y, are called sex chromosomes because they help determine whether a person ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Genetics
Medical genetics is the branch tics in that human genetics is a field of scientific research that may or may not apply to medicine, while medical genetics refers to the application of genetics to medical care. For example, research on the causes and inheritance of genetic disorders would be considered within both human genetics and medical genetics, while the diagnosis, management, and counselling people with genetic disorders would be considered part of medical genetics. In contrast, the study of typically non-medical phenotypes such as the genetics of eye color would be considered part of human genetics, but not necessarily relevant to medical genetics (except in situations such as albinism). ''Genetic medicine'' is a newer term for medical genetics and incorporates areas such as gene therapy, personalized medicine, and the rapidly emerging new medical specialty, predictive medicine. Scope Medical genetics encompasses many different areas, including clinical practice of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orofaciodigital Syndrome 1
Orofaciodigital syndrome 1 (OFD1), also called Papillon-League and Psaume syndrome, is an X-linked congenital disorder characterized by malformations of the face, oral cavity, and digits with polycystic kidney disease and variable involvement of the central nervous system. Cause Orofaciodigital syndrome type 1 is caused by mutations in the OFD1 gene. OFD1 localizes to both centrosomes and basal bodies within the human genetic cellular structure. This suggests that this syndrome may fall into a broad category of ciliary diseases. The ciliary organelles are present in many cellular types throughout the human body. Cilia defects adversely affect numerous critical developmental signaling pathways essential to cellular development. Other types include: * * * * Relation to other rare genetic disorders Recent findings in genetic research have suggested that a large number of genetic disorders, both genetic syndromes and genetic diseases, that were not previously identif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Obstetric Ultrasonography
Obstetric ultrasonography, or prenatal ultrasound, is the use of medical ultrasonography in pregnancy, in which sound waves are used to create real-time visual images of the developing embryo or fetus in the uterus (womb). The procedure is a standard part of prenatal care in many countries, as it can provide a variety of information about the health of the mother, the timing and progress of the pregnancy, and the health and development of the embryo or fetus. The International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) recommends that pregnant women have routine obstetric ultrasounds between 18 weeks' and 22 weeks' gestational age (the anatomy scan) in order to confirm pregnancy dating, to measure the fetus so that growth abnormalities can be recognized quickly later in pregnancy, and to assess for congenital malformations and multiple pregnancies (twins, etc). Additionally, the ISUOG recommends that pregnant patients who desire genetic testing have obstetric ultra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noonan Syndrome
Noonan syndrome (NS) is a genetic disorder that may present with mildly unusual facial features, short height, congenital heart disease, bleeding problems, and skeletal malformations. Facial features include widely spaced eyes, light-colored eyes, low-set ears, a short neck, and a small lower jaw. Heart problems may include pulmonary valve stenosis. The breast bone may either protrude or be sunken, while the spine may be abnormally curved. Intelligence in the syndrome is often normal. Complications of NS can include leukemia. A number of genetic mutations can result in Noonan syndrome. The condition may be inherited from a person's parents as an autosomal dominant condition or occur as a new mutation. Noonan syndrome is a type of RASopathy, the underlying mechanism for which involves overactivation within the RAS/MAPK cell signaling pathway. The diagnosis may be suspected based on symptoms, medical imaging, and blood tests. Confirmation may be achieved with genetic tes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
