Down Syndrome History

Down Syndrome, also known as trisomy 21, is a genetic disorder in which a baby is born with an extra chromosome. A baby is usually identified at birth through observation of a set of common physical characteristics. They include having slanted eyes, a pushed in face, and “Brushfield spots” [white/gray spots that appear in the iris of people with down syndrome]. In the 1930’s down syndrome was not treated very well, however many changes in the medical field has led to a better treatment of those who have this illness.

Down syndrome is named after Dr. J.L. Down, who first discovered and studied the condition. It is part of a large number of disabilities known as intellectual disabilities. Down syndrome is present at birth and individuals are usually diagnosed during pregnancy or shortly after birth. There are three types of Down syndrome. The most common of these involves an extra number 21 chromosome, which gives the individual 47 instead of 46 total chromosomes. A chromosome breaking and then reattaching to another chromosome characterizes translocation, which is the second type of Down syndrome. The third type, nondisjunction occurs when a pair of chromosomes fail to separate properly during nuclear division. Individuals with this disability usually

Down syndrome is an intellectual disability that is a result of a person being born with an extra chromosome, specifically chromosome 21. Down syndrome is the most common intellectual disability affecting approximately 1 in every 1000 births (Asim, Kumar, Muthuswamy, Jain, & Agarwal, 2015). Research has found a direct link between the age of the mother and the possibility that the baby will be born with Down syndrome, with the occurrence of Down syndrome increasing proportionally with the increased age of the mother (Asim, 2015). This condition can cause both intellectual (cognitive) and physical impairments that can range from moderate to severe (Crosta, 2016). People with Down syndrome have physical impairments such as a flat face, little to no neck, small ears, slated eyes, shorter than normal limbs and they tend to have low muscle tone (Asim, 2015). Children with Down syndrome tend to have a slower development of natural movements such as sitting, crawling and walking (Crosta, 2015). Intellectually people with Down syndrome tend to have a below average intelligence and most often they need extra assistance when attending school (Asim, 2015).

The genetic disorder of Trisomy 21, or Down syndrome is one that has often interested me. I understand that many children born with his genetic disorder can in fact live a full life, often with assistance. When answering the question of what exactly Down syndrome is, a good definition can be one describing this disorder as a genetic condition where a person has an extra 21st chromosome. The typical person has 46 chromosomes, therefore the person born with Down syndrome has 47. This extra chromosome brings with it some physical and cognitive characteristics that include mild to severe cognitive delay, low muscle tone, stunted growth, an easily identifiable upward slant to the eyes, generally a deep crease across the center of the palm and the appearance of a flat face. We have to keep in mind however, that each person with Down syndrome is an individual and might have some of these characteristics to different degrees, or possibly none at all.

One of the most common genetic birth defects is Down syndrome which is a congenital disorder caused from a chromosome defect. It causes impairments and physical abnormalities. This is a condition where a child is born with an extra copy of their 21st chromosome. According to the National Down Syndrome Society (NDSS), 1 in 700 babies are born with DS. There is not an exact cause of how DS happens but there is an explanation as to what happens. When there is any case of reproduction, genes from both parents are passed to the children. Within these genes there are chromosomes and the child is supposed to receive 23 pairs of chromosomes or 46 total. Children with DS end up with 3 copies or an extra partial copy of chromosome 21 instead of 2

Down syndrome (known as Trisomy 21) is a genetic disorder caused when cell division results in extra genetic material from chromosome 21. This genetic disorder occurs in about 1 of 800 live births. Down syndrome was first characterized a separate form of mental disability by John Langdon Down in 1862. By the 20th century the disability had become the most recognizable form of mental disability. These individuals have gone through a lot. In ancient times, many infants with this disability were killed or abandoned. The people with Down syndrome used to be called Mongolian idiots and the syndrome was called mongolism. This comes from the people thinking that Down syndrome individuals resembled Mongolians. It doesn’t only affect the individual

In 1866, a British physician, John Langdon Down, for whom the syndrome is named, first described Down Syndrome, as ?Mongolism.? Down was a superintendent of an asylum for children with mental retardation. He observed a set of children with common features who were distinct from children with mental retardation. The term Down Syndrome didn?t become the accepted term until the early 1970s. More was learned about the condition in 1959, when French Pediatrician/Geneticist Profess Jerome Lejeune discovered that individual with Down syndrome had an extra chromosome. Shortly thereafter, chromosome studies were developed to confirm the diagnosis of Down syndrome (Wright, 2011).

spread further apart, and are super flexible. This disorder varies in several different ways; it

Down syndrome was fist described by John Langdon Down in 1866, but the earliest depiction of someone with Down syndrome was a painting dated in 1515. John Langdon Down had said it was only a disorder, but did not understand how it occurs. The cause was later discovered in 1959.

Down syndrome is a genetic defect attributed to an abnormality of the human chromosome 21. The National Down Syndrome Society (NDSS), a national advocate organization for the value, acceptance and inclusion of people with Down syndrome, notes that modern research has successfully identified three types of Down syndrome. The NDSS reports that Nondisjunction Trisomy 21, in which there are three copies of chromosome 21 instead of two, is the most common type of Down syndrome. Prior to or at the point of conception, a pair of 21st chromosomes in either the

“Keep calm, it’s only an extra chromosome.” These “Keep Calm” sayings are flooding our society, however, some of them have more serious content behind them. This “Keep Calm” statement is referring to a lifelong disorder known as Down syndrome or trisomy 21. Down syndrome (DS) can affect multiple areas of a person’s development both mentally and physically. This paper looks at how to detect DS as early as the second trimester of pregnancy, the effects it has on early childhood development, and the effects on a person’s mental abilities.

Down Syndrome (DS) or trisomy 21 is a condition where “the third copy of chromosome 21 disturbs the expression of all DNA in the genome” (Study revises cause of down syndrome, 2014, p.1). This genetic condition is responsible for

Trisomy 21(Down Syndrome) is one of the most common types of chromosomal mutation. First published by John Langdon Down in 1866 and associated with chromosomes in 1959 by Jerome Lejeune, this mutation has affected thousands of infants around the world. The main cause for Down Syndrome is the formation of a 2 chromosome coming together in addition to another that does not belong. This produces extra genetic material. This occurs in the 21st chromosome of a human karyotype and this causes the newborn to have 47 chromosomes instead of the normal 46 chromosomes. So when the egg and the sperm come together there is an uneven amount of chromosomes coming from each parent.

Down syndrome, also known as trisomy 21, occurs when a child is born with three copies chromosome 21, as you can see in Figure 1. This can be caused by three different processes; nondisjunction, mosaicism, or translocation. Nondisjunction occurs during the reduction of chromosomes, from 46 to 23, after the egg and sperm have combined, causing one parent to pass on 24 instead of 23. In the case of Down syndrome, the extra chromosome is chromosome 21. Mosaicism is a rare occurrence, happening “in approximately one to two percent of Down syndrome cases” (Johnson, 2013). Initially, the correct number of chromosomes is passed on from the parents, but during the phase following fertilization, when the cells are dividing quickly, one cell divides

Typically, the nucleus of each cell stores forty-six chromosomes. Half of these chromosomes derive from each parent cell. However, in those with Down syndrome, the cells contain forty-seven chromosomes. Researchers’ knowledge of the etiology of Down syndrome has grown since it was first described in 1866 by John Langon Down (National Down Syndrome Society, 2012). According to the National Down Syndrome Association (2012), 95% of the Down syndrome cases are caused by a fault in cell division. Although it is clear that this disorder occurs because of an alteration during cell division, the cause as to why this occurs is unknown. However, the pathogenesis of this disorder is clear. The pathogenesis of this disorder begins with nondisjunction during meiosis, which is failure of the chromosomes to separate. Today, it is known that there