Trisomy 21 And Down Syndrome

The preposition of cells seems to exhibit the severity of trisomy. The age of the parents seems to increase the contributing aspect to Down syndrome. Women thirty-five and older have given birth to sixteen percent of babies, which over half were born with Down syndrome. Expects have conducted different experiments to try and explain this, the first being the “older egg” hypothesis. With age the ova either changes due to time or for the reason of increased exposure to potentially hazardous biological and environmental conditions (p89). During ovulation the egg cells being released in later childbearing aged women are more susceptible to chromosomal errors as most are undergoing the last stages of meiosis. Other expects have a hypothesis of the “relaxed selection”, which shows older mothers, contrary to younger mothers, are less likely to unconsciously terminate the fetus with trisomy 21 chromosomes. Another view is egg cells with the extra chromosomes are less likely to be selected but as the women ages more egg cells with extra chromosomes are present and there are more to choose from. The age of the father can also be a

Low muscle tone. Small stature. Upward Slant to the eyes. Single deep crease across the center of the palm. These are a few common physical traits of individuals with Down syndrome. However, every person with Down syndrome is unique and portrays each characteristic at a different degree. Individuals with Down syndrome have an extra chromosome 21. The additional genetic material alters childhood development and causes characteristics associated with the disease. Non-invasive prenatal tests, known as NIPT, analyze the amount of chromosome 21 in the mother’s blood at 10 weeks pregnant. This eugenical testing leads to the extermination of those with Down syndrome. Not only have the abortions rates increased since

When a baby is conceived, the baby receives 23 chromosomes from each parent, equaling 46 chromosomes. Sometimes during this creation a sperm or egg cell can causes that cell to contain 24 chromosomes. When this abnormal cell is included in the conception of a baby, that baby will have 47 chromosomes. The extra chromosome causes Down syndrome. After fertilization; cells start to divide rapidly. Depending on how the cell divides determines what type of Down syndrome the child has. Mosaic Down syndrome is obtained when a cell divides abnormally, creating a string of cells with the extra chromosome. A child with Mosaic Down syndrome has both cells: the normal 46 chromosomes, and the Down syndrome 47 chromosomes. It is believed that babies with Mosaic Down syndrome experience mild symptoms of the disorder.

Down Syndrome (otherwise called Trisomy 21) is the most widely recognized hereditary issues that causes a long lasting scholarly disability, formative postponements and different issues. Down Syndrome influences individuals of any age, races, and financial levels. It is a standout amongst the most as often as possible happening chromosomal variations from the norm, happening once in each 800 to 1000 live births. More than 350, 000 individuals in the United States alone have Down Syndrome. My objective for this paper is to discuss the three unique sorts of Down Syndrome and to discuss the contrasts between them.

Trisomy Down Syndrome happens when there are three 21 chromosomes as opposed to the normal two. This is a result of either the sperm or egg failing to separate causing a replication in every cell of the body. Another type called Robertsonian Translocation happens when part of chromosome 21 is translocated to another chromosome to the reproductive cells to the parent or early development of the child. This type accounts for about 4% of all cases of down syndrome. Mosaic is a form of down syndrome when the extra chromosome 21 is found only in some of the body's cells. “Mosaicism is the least common form of Down syndrome and accounts for only about 1% of all cases of Down syndrome.”

This means that babies with down syndrome have an extra chromosome, chromosome 47. Some symptoms of the disorder is physical features such as, flat facial profile, upward slant to eyes, small ears, protruding tongue, and your child will have low muscle tone. Other symptoms include, problems with hearing and vision, being cross eyed, having breathing problems, taking longer than normal to reach childhood milestones and take care of themselves, mild to moderate learning impairment, and growing at a slower rate.

There are 3 types of Downs syndrome, translocation; standard trisomy 21 and mosaicism. Translocation is caused when a piece of chromosome 21 is located on another chromosome such as chromosome 14. The person with Translocation Trisomy 21 will have 46 chromosomes but will have the genetic material of 47 chromosomes. The person with Translocation Trisomy 21 will exhibit all the same characteristics of a person with Standard Trisomy 21 since they have three copies of chromosome 21. Translocation occurs between 3% and 5% of cases of Down syndrome. Standard trisomy 21 is the most frequent form of downs syndrome. Those affected by trisomy 21 will have 47 chromosomes in every cell as opposed to 46 like normal. Mosaicism is similar to standard trisomy

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

Down syndrome is usually every 1 in 400 children if the mother is about 35-40 years old, and

In Down syndrome, a person most often inherits two copies of chromosome 21 from the mother and one chromosome 21 from the father for a total of three chromosomes 21. If a baby inherits the chromosome with the extra genes from chromosome 21, then the child will have Down syndrome. About 2% to 4% of people with Down syndrome inherit additional genes from chromosome 21, but not in every cell of the body. These individuals may, for example, have inherited extra genes from chromosome 21 in their bone marrow causing an abnormal increase rate of blood cell production which is the cause of Leukemia Cancer. (Schainman 36)

Down syndrome is a chromosomal disorder which occurs in 1 out of every 800 live births ((T. Crandell, C. Crandell & Vander Zanden, 2012, p.81). Most Down patients have a condition called trisomy 21, or 3 copies of the 21st chromosome. This results in an individual with 47 total chromosomes instead of 46 that are normal (Crandell et al., 2012, p.81). This extra chromosome alters typical human

There are over 400,000 individuals with Downs Syndrome: reminder that Down Syndrome is also called Trisomy 21, which is an extra x chromosome on the 22nd chromosome. Given the amount of individuals with Downs Syndrome, it is key that we acknowledge that statistic and foster ways in which we make these individuals lives, and overall quality of life better.

Trisomy 21 is a result of chromosome non-disjunction in one of the meiotic cell divisions. The non-disjunction event can occur in either parent, but more likely to occur in females. Congenital birth defects are difficult to treat but with the prevalence of Down Syndrome, numerous research projects are being carried out by Down Syndrome Research and Treatment Foundation (DSRTF). Some of the studies are as follows:

Trisomy 21 is caused by an error in cell division which is called nondisjunction. Nondisjunction results when the embryo gets three copies of chromosome 21 instead of two. This usually occurs at or prior to conception, a pair of 21st chromosomes in either the sperm or the eggs fails to separate. Since this occurs so early on, the extra chromosome is then replicated in every cell of the body. This type of Down syndrome accounts for 95% of cases (“What”). Translocation accounts for about 4% of cases. In this types the total number of chromosomes in the cells remain 46, but an additional full or partial copy of chromosome 21 attaches to another chromosome (usually 14). The presence of the extra full or partial chromosome 21 causes the characteristics of Down syndrome (“What”). Mosaicism or mosaic Down syndrome is a mixture of the two other types. It is characterized by a mixture of two types of cells, some containing the usual 46 chromosomes and some containing 47. The cells that do contain 47 chromosomes contain an extra chromosome 21. This type accounts for only 1% of all the cases of Down syndrome. Some research has shown that individuals with mosaic Down syndrome may have fewer characteristics of Down syndrome that those with other types

In 1862, John Langdon Down, an English physician, first described those with Down’s Syndrome as “mongoloids” as he believed those with the condition appeared visually similar to people within the Blumenbach’s Mongolian race (Dr Ananya Mandal, 2014). However, in the 1970s, the term Down’s Syndrome replaced mongoloids as it was inaccurate (Dr Ananya Mandal, 2014). During the 20th Century, people with Down’s Syndrome were commonly seperated from society and sent to institutions (Dr Ananya Mandal, 2014). In addition, those with Down’s Syndrome were forcefully sterilized during the 20th Century in an attempt to rid them from the disease (Dr Ananya Mandal, 2014). In 1959, Jérôme Lejeune, a French Pediatrist, discovered that people with Down’s Syndrome have an extra 21st chromosome (Dr Ananya Mandal, 2014). This is where the term Trisomy 21 derrived from which is another name for Down’s Syndrome.