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Down's syndrome (trisomy 21, mongolism)
The Down's syndrome is the most frequent congenital illness whose cause is a chromosome anomaly. In every nucleus of their body cells 47 chromosomes instead of 46. the 21st chromosome the fallen ill is available three times and causes the below described disease features have. Three forms of the trisomy 21 are distinguished. The free trisomy 21 happens to 95%. The supernumerary chromosome can be seen free. It is a hereditarily conditional translocation trisomy at 2.5% the fallen ill. The additional chromosome or at least an essential component of this one is (most chromosome 14, 21 or 22) fastened to another autosome. Both forms of the trisomy draw solid physical effects after themselves. 2.5% of the persons affected are affected by a mosaic trisomy also. The markedness of the illness of the typical Down's syndrome also varies cells with trisomy 21. depending on share of the trisomy cells up to an almost normal phenotype and intellect be found besides cells with a normal chromosome set. If one talks about the Down's syndrome, the free trisomy is meant mostly.
The birth of a child falls on living given birth about 700 with Down's syndrome. The risk of being having a mongoloid baby increases with the giving birth age of the mother. The probability 0.5 is 1.3% at 40 up to 45-year mothers 1.3, 4.4%, at 35 up to 40-year mothers. But also quite young women can take children to the world with Down's syndrome. The age of the father plays year of life a role approximately as of 50.
The free trisomy isn't hereditary, however, statistical examinations have shown that the repetition risk increases by 1% after the birth of a child with Down's syndrome for further brothers and sisters children.
The cause of the Down's syndrome is a chromosome disturbance. The chromosomes are carriers of our genetic information. Every man has 46 chromosomes (diploid chromosome set) in the nucleus of his cells of which 23 of paternal (haploid chromosome set) and 23 maternal insertion are. You ares numbered in are karyogram, are representation of The chromosome break off, from 1 to 23. is the same number always given to a pair of chromosomes which show approximately the same morphological characteristics and have the homogeneous genes in perhaps different expressions. One also describes it as homologous chromosomes.
At the formation of the sexual cells (ovum and sperm cell) the diploid chromosome set (46 chromosomes) is reduced to the haploid chromosome set (23 chromosomes) in a so-called meiotic division. The homologous chromosomes are separated. An error can happen at the meiotic division now. The chromosome with the number 21 is in either the egg or sperm cell instead of once available twice. After the nuclear fusion of the two sexual cells it is then available in the stimulated ovum (zygote) three times! The name also therefore comes: Tri (three) somy (chromosome).
Already with newborn childs the clinical picture of the Down's syndrome is recognizable. You have a round face, the eyes stand far from each other with palpebral fissures provided at an angle, the top eyelid has moved to the nose. Passes a similarity to the Mongolian race! The hands are broad with short fingers and about the hand inside a continuous furrow (simian crease) goes. The toe gap between the 1st and 2nd toes is extended (sandal gap). Small, the muscles are mongoloid children and the connective tissue is developed weakly loose so that leave for example the joints over-ways himself. The narrow, high palate and a too big tongue are also characteristic for the Down's syndrome. It frequently looks out of the mouth. Drinking problems in the infancy can be the consequence. Fell ill wax more slowly and reach a height which is below the average.
Children with Down's syndrome are mentally handicapped. Your physical and mental development goes delayedly.
At trisomy 21 also there is a good chance for a possible physical qualified sense. 50 per cent of the children have a heart defect. Disturbances as well aren't a rareness in the digestion tract. The infection vulnerability of the children concerned is increased. You get primarily more lightly infections at the respiratory systems. Your immune system is underdeveloped. You therefore also more frequently than healthy children tend to leukemia, a shape of leukemia. Hearing and seeing problems also appear at this illness increased. Problems in the communicative area can be the consequence. It comes speech development or the speech is therefore often indistinct to a delayed one sometimes, too. The abbreviated life expectancy is determined by the heaviness of the heart defect and the markedness of the immunodeficiency essentially.
The results of the illness, such as drinking problems in the infancy or the speech retardation, are, however, different and dependent on the degree of their handicap from child to child.
The diagnosis of the illness is made obviously with the external features. The diagnosis confirms a chromosome analysis from lymphocytes of the blood and information about the species gives to the trisomy (free trisomy, translocation trisomy, mosaic trisomy).
Gives examination methods a row already in the prenatal diagnostics to state trisomy 21 at the unborn one. The so-called dorsonuchale edema of interest is at the 1st ultrasound Screening between the 9th and 12th pregnancy weeks. So a water accumulation which is visible in the ultrasonogram as a nape fold is described in the nape. It can be a reference to the genetic illness. This check-up is offered to all pregnant women. Also be able to pregnant women make a chrionzottenbiopsie (to miscarriage risk 0.5 to 2%) as of the 35th year of life between the 10th and 12th pregnancy weeks to exclude the trisomy 21 or it is the possibility a fetus water puncture as of 16 pregnancy week (miscarriage risk 0.5 to 1%). With the help of one of these tests the Down's syndrome can be recognized at the unborn one with a 99.9 per cent probability. An abortion due to a medical indication is permitted in Germany at the trisomy 21 and lies in the power of decision of the pregnant woman concerned.
There isn't a causative therapy at the Down's syndrome. At present, it isn't possible to block or to turn off the supernumerary chromosome.
A specific support and care at full term can help the mongoloid children, however, and make the life easier for them one.
The physical impairments, like heart defects or intestine malformations, can be treated operatively. The high, pointed palate and tooth malpositions can be given therapy by palate plates at the orthodontist, for example.
Early recognition and treatment of the hearing problems with the children concerned can improve the speech development fundamentally. The language instruction should start as early as possible. Visual elements, like sign language and "reading early", are used.
The loose connective tissue and the too weak muscles get strengthened, coarse and a fine motoric motion coordination promoted by physiotherapy.
The education has positive influence on the mental retardation in the family. Social behaviors can be studied and practiced here. Important is, however, the acceptance of the mongoloid children to this by the family and its environment. You are really lovable and clinging and can develop a distinctive social behavior. You need however patient instruction, good schools or day places in which they get well-being educational and promoted by ergotherapy and physiotherapy.
It has passed away individually, which stage of development mongoloid children achieve. Some need their life at everyday things like eating for a long time and attracting help, others can carry out simple works and earn money itself.
These informations may be considered a substitute for a piece of medical advice in no case. The content of health-illness.com doesn't can and may be put into any case to make diagnoses or carry out self medical treatment independently.
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