...Down syndrome (DS) or Down's syndrome, also known as trisomy 21, is a chromosomal condition caused by the presence of all or part of a third copy of chromosome 21.[1] Down syndrome is the most common chromosome abnormality in humans.[2] It is typically associated with a delay in cognitive ability (mental retardation, or MR) and physical growth, and a particular set of facial characteristics.[1] The average IQ of young adults with Down syndrome is around 50, compared to children without the condition with an IQ of 100.[1][3] (MR has historically been defined as an IQ below 70.) A large proportion of individuals with Down syndrome have a severe degree of intellectual disability.[1] Down syndrome is named after John Langdon Down, the British physician who described the syndrome in 1866.[4] The condition was clinically described earlier in the 19th century by Jean Etienne Dominique Esquirol in 1838 and Edouard Seguin in 1844.[5] Down syndrome was identified as a chromosome 21 trisomy by Dr. Jérôme Lejeune in 1959. Down syndrome can be identified in a baby at birth, or even before birth by prenatal screening.[1][6] Pregnancies with this diagnosis are often terminated.[7] The CDC estimates that about one of every 691 babies born in the United States each year is born with Down syndrome.[8] Many children with Down syndrome graduate from high school and can do paid work,[9] and some participate in post-secondary education as well.[10] Education and proper care has been shown...
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...THE REPORT DOWN SYNDROME ( TRISOMY 21 ) Down syndrome is a developmental disorder caused by an extra copy of chromosome 21 (which is why the disorder is also called "trisomy 21"). Having an extra copy of this chromosome means that each gene may be producing more protein product than normal. Cells seem to tolerate this better than having not enough protein, or having altered protein due to a mutation in the DNA sequence. However, producing too much protein can also have serious consequences, as seen in Down syndrome. Genes on chromosome 21 that specifically contribute to the various symptoms of Down syndrome are now being identified. Down syndrome is typically caused by what is called nondisjunction. If a pair of number 21 chromosomes fails to separate during the formation of an egg (or sperm), this is referred to as nondisjunction. When that egg unites with a normal sperm to form an embryo, that embryo ends up with three copies of chromosome 21 instead of the normal two. The extra chromosome is then copied in every cell of the baby's body. Interestingly, nondisjunction events seem to occur more frequently in older women. This may explain why the risk of having a baby with Down syndrome is greater among mothers age 35 and older. In rare cases Down syndrome is caused by a Robertsonian translocation, which occurs when the long arm of chromosome 21 breaks off and attaches to another chromosome at the centromere. The carrier of such a translocation will...
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...Down Syndrome Down syndrome is an issue with the chromosomes in a human that not only causes the child stress but additional stress to the parents. The human body is made of cells. All cells contain a center, called a nucleus, in which genes are stored. Genes, which carry the codes responsible for all our inherited characteristics, are grouped along rod-like structures called chromosomes. Normally, the nucleus of each cell contains 23 pairs of chromosomes, half of which are inherited from each parent. Down syndrome occurs when some or all of a person’s cells have an extra full or partial copy of chromosome 21. The most common form of Down syndrome is known as Trisomy 21. Individuals with Trisomy 21 have 47 chromosomes instead of the usual 46 in each of their cells. The condition results from an error in cell division called non-disjunction. Prior to or at conception, a pair of 21st chromosomes in either the sperm or the egg fails to separate. As the embryo develops, the extra chromosome is replicated in every cell of the body. This error in cell division is responsible for 95 percent of all cases of Down syndrome. Having an extra copy of this chromosome means that each gene may be producing more protein product than normal. Cells seem to tolerate this better than having not enough protein, or having altered protein due to a mutation in the DNA sequence. The condition leads to impairments in both cognitive ability and physical growth that range from mild to moderate...
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...of Literature 25 May 2010 Life with Down syndrome “ Down syndrome is a genetic disorder that causes mental retardation and physical it is caused by the presence of an extra copy of chromosome number 21” (“Down syndrome” par.1). Down syndrome is the most frequent genetic cause of mild to moderate intellectual and developmental, it occurs in out 1 of 800 births (“Down syndrome” par.1). The discovery of Down syndrome was in 1866 by Dr. John Langdon Haydon Down, who worked in an English hospital for mental disabilities. Dr. Down had notice that many of the people cared for in the hospital shared certain physical features that is related to Down syndrome. About 100 years later, a French scientist figured out it was genetics that caused the problem (“Thumbs up for Dr. Down” par. 1). Life with Down syndrome, physical and mental disability caused by extra chromosome, creates life challenges from birth to adulthood. Being born with Down syndrome is such challenge for new born babies. “During the early years of life children with Down syndrome are ten times more likely than other children to develop a potentially fatal disease…or defective development of the spinal cord” (“Infants and preschool children” par.21). About half of babies with Down syndrome are born with heart defects, which mean their hearts, grow differently and don’t work as they should usually, these problems can be fixed by surgery (“Down syndrome” par.3). “Kids with Down syndrome are more likely to get infections that...
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...Down syndrome [Author Name(s), First M. Last, Omit Titles and Degrees] [Institutional Affiliation(s)] Author Note [Include any grant/funding information and a complete correspondence address.] Introduction: Down syndrome is a disorder which arises due to defects in chromosomes. It causes intellectual disabilities and physical abnormalities. Short stature and broad faces are the characteristics of this disorder. There are many causes of this disorder, but scientists put an emphasis of chromosomal abnormality and protein sequences the most. Role of chromosomes: The causes of the presence of this extra chromosome are still under consideration. Usually, maternal age is linked to this disorder. Due to higher birth rates in younger women, 80% of children with Down syndrome are born to women under 35 years of age. However, the exact cause of this disorder is still unknown. There are different types of down syndromes, but the causal factor is same. The human cell has 46 chromosomes in each cell but in this disorder the case is different. One of the chromosomes is called chromosome 21 which is known to be the leading cause of Down syndrome. All the people suffering from this disorder have an extra part of chromosomes 21. The presence of this extra chromosome changes the overall developmental pattern of the individual. A process causes the disorder we call nondisjunction. Nondisjunction happens when the pair of chromosomes do not get separated from each other during egg...
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...Down syndrome, also known as Trisomy 21, is a condition in which extra genetic material causes delays in the way a child develops, both mentally and physically. It affects about 1 in every 800 babies born in the United States. A person with Down syndrome has 47 chromosomes instead of the usual 46. The physical features and medical problems can vary widely from child to child. While some kids with Down syndrome need a lot of medical attention, others live healthy land fulfilling lives. Every human being with Down syndrome has a widely recognized appearance, flattened nose, single crease in the palm of the hand, Small ears, small mouth, upward slanting eyes, and wide short hands with short fingers. The physical development of people with Down syndrome is often slower than normal. Most of the children who are born with this disorder never each their average adult height. They may also have delayed mental and social development. Some of the common problems include impulsive behavior, poor judgement, short attention span, and slow learning. In some cases, when children with Down syndrome become aware of their limitations they may feel frustrated and angry. Obesity can become a problem for older children and adults. Getting plenty of activity and avoiding high-calorie foods are important. Before beginning sports activities, the child's neck and hips should be examined. Behavioral training can help people with Down syndrome and their families deal with the frustration, anger, and compulsive...
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...What is Down syndrome? Down syndrome is genetic disorder that causes lifelong mental retardation, developmental delays and other problems. Down syndrome varies in severity, so development problems range from moderate to serious. Down syndrome is the most common genetic cause of severe learning disabilities in children, occurring in one in every 700 to 800 infants. Increased understanding of Down syndrome and early interventions make a big difference in the lives of both children and adults with Down syndrome. Down syndrome is also known as Trisomy 21 syndrome. Trisomy 21 is due to an extra copy of chromosomes number 21. Instead of having the normal two copies chromosomes number 21, the person with Down syndrome has three copies of chromosomes 21. Meaning normally a fertilized egg has 23 pairs of chromosomes. In most people with Down syndrome, there is an extra copy of chromosome 21. (Rogers, 2007, pg.6) The formal story began in 1866, when a physician named John Langdon Down published an essay in England in which he described a set of children with common features who were distinct from other children with mental retardation. Down was superintendent of an asylum for children with mental retardation in Surrey, England when he made the first distinction between children who were cretins (later to be found to have hypothyroidism) and what he referred to as "Mongoloids." Down based this unfortunate name on his notion that these children looked like people from Mongolia,...
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...How Genetics Influence Down Syndrome PSY 104 Professor Vincent July 7, 2013 How Genetics Influence Down Syndrome Genetics play such an vital role in our development. Every individual carries genes from their mother and their father. Characteristics such as height, eye color, if we have curly or straight hair are all determined through the our genes and specifically our chromosomes. Many times, parents inadvertently pass genes on to their children through their DNA that may contribute to developmental disorders such as Down Syndrome. In this paper, I will explain the role of genetics and how it plays a part in development. I will also explain how the genes of two parents can influence the traits and characteristics of their offspring. Every person has genes and chromosomes located in every cell of their body. Those genes and chromosomes are what make us unique and different. Almost all of a person's traits, from their eye color to what type of hair they will have are coded in their genes (Beck, 2000). Genes and chromosomes come in pairs, with one member of each pair coming at conception from the father and the other from the mother. Normally, at the time of conception a baby inherits genetic information from its parents in the form of 46 chromosomes: 23 from the mother and 23 from the father (Skallerup, 2008). When a child has an extra chromosome for a total of 47 chromosomes instead of 46, they are believed to have Down Syndrome. The genetic material children carry play...
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...William has Down syndrome as well as a severe developmental delay. Down syndrome is an extra chromosome that develops when the baby is in their mother’s womb (Evans-Martin, 2009). As Evans-Martin (2009) states children with down syndrome have different physical characteristics compared to a child without down syndrome. For Instance, William joints are looser and he is able to put his feet into his mouth with ease and he tends to lay on the floor with his feet behind his head throughout the day. According to Evan-Martin (2009) William displays the classic features of a child with down syndrome, for instance the middle of his face is flatter than normal and he has a smaller nose which is also flat on the bridge. William has an epicanthal fold...
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...Down syndrome Approximately 220,000 babies are born with down syndrome every year. That is 1 in every 800 babies. A average person is born with 23 pairing or 46 total chromosomes. A person born with down syndrome usually has 47 chromosomes. When down syndrome occurs the reason is because of an extra copy of the 21st chromosome in every cell. In medical terms “trisomy” refers to having an extra copy of a chromosome. The proper name for down syndrome is Trisomy 21 because of the extra copy of the 21st chromosome ("Facts about Down Syndrome”). Mosaicism occurs when a child is born with an extra chromosome in some but not all of their cells. Mosaicism normally has less severe symptoms than trisomy 21. Translocation down syndrome occurs...
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...Down syndrome occurs when someone has has a full or partial copy of chromosome 21 the cause of down syndrome is called nondisjunction, nondisjunction is what happens when chromosomes fail to separate properly thus having an extra strand of dna on trisome 21, down syndrome is also known as trisomy 21. Down syndrome affects every 1 in 691 babies in america which make it the most common chromosomal disorder in the world. yet despite it being the most common in the world there is still no cure for down syndrome, doctors have found that some treatments can help. down syndrome causes intellectual impairment and and physical abnormalities, physical abnormalities include short stature, broad facial profile. intellectual impairment included lack ability...
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...A diagnosis of Down’s Syndrome should not be allowed as a reason to terminate a pregnancy. Down syndrome is when a baby is born with an extra chromosome. Usually, a baby has 46 chromosomes, but a baby born with Down syndrome have an extra copy of chromosome 21, and as a result physical and mental issues occur. Children with Down syndrome have varying degrees of physical differences; such as a flatter face, slanted eyes, smaller stature, etc. They can also have some developmental disabilities and medical problems; such as heart defects, stomach problems, eye issues, etc. People who agree with this statement believe that abortion due to down syndrome is discrimination, that no matter the circumstance you have the right to life, they can be loving people too, through the years the quality of life for them is better and there are...
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...are affected from down syndrome. Though, all of these 400,000 people suffer from the same genetic disorder, each person that is affected are different in their personality, needs, and individuality. Down syndrome doesn’t just affect the person’s looks and genetic mismatches, but also the way they live life and the treatment they need and will have to undergo. In addition, there are 3 different types of down syndrome. Trisomy 21, Translocation and Mosaicism. Standard Trisomy 21 is when an extra 21st chromosome is duplicated. The extra copy could come from the egg or sperm cell. Translocation is caused when pieces of the 21st chromosome is located on another chromosome such as 14 or 17. And finally Mosaicism, Mosaicism is the presence of multiple types of cells with different genotypes in one individual cell. An example of this is when, some cells contain the usual 46 chromosome but will also contain genetic material of 47 as well. (What is Down Syndrome?pg.2-3). All of these types are all genetic mutations of...
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...baby has Down's syndrome By DAILY MAIL REPORTER UPDATED: 12:13 GMT, 7 March 2011 Doctors have developed a blood test to check unborn babies for Down’s syndrome. The approach could save pregnant women from having the invasive examinations currently available, which raise the risk of miscarriage. Current blood tests can only tell if a baby is at risk of Down's Syndrome. Scientists from Cyprus, Greece and Britain said the new technique correctly identified 14 Down syndrome cases and 26 normal foetuses in a blind test. They believe it will also be possible to diagnose the condition earlier on. Study author Philippos Patsalis, of the Cyprus Institute of Neurology and Genetics, said: 'The method is simple and fast and easy to perform in every genetic diagnostic lab worldwide because it does not require expensive equipment, software or special infrastructure. 'The test is the first worldwide to demonstrate 100 per cent sensitivity and 100 per cent specificity in all normal and Down's syndrome pregnancies examined.' Down's syndrome is a genetic disorder that causes physical and learning disabilities and raises the risk of heart disease. Infants with the condition have three copies of the Chromosome 21 instead of the normal two. It affects about one in every 700 live births but women of 40 are 16 times more likely to have a Down's child than a 25-year-old. At present all pregnant women are offered screening to see if their baby is at risk of Down's syndrome. For a firm diagnosis...
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... about 6,000 infants are born with Down syndrome, which is roughly 1 in 700. Down syndrome is a genetic chromosome disorder causing developmental and intellectual delays. Therefore, many families, in the early twentieth century, thought that children with Down syndrome were less human and required care that the families could not do. Many children with Down syndrome were put into intuitions soon after birth. These children were put into large institutions so that society would not have to see the horror of their lives. Down syndrome is a genetic disorder that causes developmental and intellectual delays, abnormal appearance, and an impact on family. Down syndrome can be diagnosed in two ways before the baby is born: parental screening, and diagnostic test. Parental screening can check if the fetus has a chance of having Down syndrome. This test does not tell you for sure if your child may have Down syndrome, just an estimate....
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