One Of The Most Common Types Of Down Syndrome

. Down syndrome is not a disease that someone catches and is not caused by difficulties during the pregnancy, it is a genetic condition. This condition is caused by the presence of an extra chromosome in the body’s cells and causes a redundant amount of proteins to be formed. All cells of the body derive from a single cell formed by the fusion of a father’s sperm and a mother’s egg. Each cell carries a nucleus full of genetic material known as genes. These genes are inherited from both the mother and father. Each cell normally contains 46 pairs of chromosomes. 23 chromosomes come from one parent and 23 from the other, hence the 46 pairs. When it comes to children with down syndrome, one of the chromosomes does not separate properly and so the

Answer: The most common form of Down syndrome is known as Trisomy 21, a condition where individuals have 47 chromosomes in each cell instead of 46. This is caused by an error in cell division called nondisjunction, which leaves a sperm or egg cell with an extra copy of chromosome 21 before or at conception. To the genes when the cell division occurs is when the extra chromosome goes to find a cell and attaches

The aetiology of Downs syndrome which means the cause of a specific disease (Mcferran, 2014). Suggests that when one of the chromosomes in reproduction do not separate properly this is when Down’s Syndrome is caused (Steven, 2005). This extra chromosome causes physical developmental defects this causes reduced muscle tone, a small mouth with a projecting tongue and eyes that slant downwards and upwards and causing the back of their head to be flat. Many babies born with Down's Syndrome are diagnosed with the condition after birth and are likely to have many physical defects for example they may have reduced muscle tone, eyes that slant upwards and outwards, a small mouth with a protruding tongue and a flat back of the head. (Hartley, 2015). Down Syndrome patients can also be afflicted with other conditions, including heart disease, Alzheimer’s disease, and leukemia (WHO, 2010). This could effect children and adults through out their life also effecting their physical and mental health.

Downs syndrome is common name for the condition known as triosomy 21. Here the triosomy indicates babies have 3 copies of a certain gene, instead of the usual two.

Down syndrome is caused by having an extra chromosome on the twenty-first chromosomal pair. People with down syndrome have forty-seven pairs of chromosomes. There are three types of down syndrome and they are Trisomy 21, Translocation, and Mosaicism. Trisomy 21 is the most common type of down syndrome. It occurs when there are three rather than two, number 21 chromosomes present in every cell of the body. Trisomy 21 accounts for ninety-five percent of the down syndrome population. Translocation unlike Trisomy 21 only accounts for four percent of the down syndrome population. In this case, part of the twenty-first chromosome breaks off during cell divas and attaches itself to another chromosome, usually chromosome 14. Mosaicism is the rarest

The etiology of Down syndrome is due to a genetic mutation within chromosome 21. There are three types of Down syndrome, which include Trisomy 21, Mosaic Down Syndrome, and Translocation Down Syndrome. Trisomy 21 occurs when there are three copies of chromosome 21 in each nucleus, instead of the usual two. This type of Down syndrome occurs 95% of the time. Mosaic Down Syndrome occurs 1% of the time and is characterized by some cells having three pairs of chromosome 21 and others having the normal two. This is caused by abnormal cell division after

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.”

There are 23 pairs of chromosomes in a normal human cell. Trisomy 21 or Down syndrome occurs when there is a third copy of chromosome 21 and causes malformation in body and brain development. Giving birth to a child with down syndrome increases as the mother ages. The odds of having a child with trisomy 21 are 1 in 1000 for women under the age of 35. This increases to 1 in 200 for women 35 and older. Thus, while not completely avoidable, it is best to have children while the mother is still under 35 to allow the child to be less likely to be born with down syndrome.

Down Syndrome is a genetic disorder that occurs when a persons 46 chromosomes abnormally divides into 47 chromosomes, creating a full or partial 3rd copy of the chromosome 21.

Trisomy 21 most commonly known as Down syndrome is a genetic disorder that causes abnormal cell division resulting an extra genetic material forming a twenty-first chromosome. No one knows for sure why Down Syndrome happens and there is no way to prevent the chromosomal error that causes it. Scientists knows that women age thirty-five and older have a significantly higher risk

Down syndrome is a congenital disorder arising from a chromosome defect, the chromosome causing the problems is Chromosome 21. Down syndrome current affect about 1 in 600-800 live births in the United States. There are about 400,000 Americans that have Down syndrome, with approximately 6,000 babies are born with this disorder each year. The disorder is thought to form during gametogenesis, during fertilization, or soon after fertilization (Daniilidis, et al. 2015). Fertilization occurs when the sperm binds to zona pellucida, then the sperm undergoes acrosome reactions which will lyses a hole in zona pellucida, and then the sperm and egg membrane fuse. Once the membranes fuse, the sperms genetic material gets released and gets combined with the egg’s chromosomes, thus resulting in a 46 chromosome fertilized egg. This is the mostly likely phase in which Down syndrome gets formed, since it is caused by a mistake in cell division during the development of the egg, sperm or embryo. The mother or the father can be the origin in which the extra partial or full chromosomes come from, but approximately only 5% have been traced to the father. Maternal age is the only risk factor that has been linked to an increased chance of Down syndrome. Down syndrome is not inherited, but 4% of translocation Down syndrome is inherited (Mayo Clinic Staff).

Down syndrome is a disease in which chromosome 21 has extra genetic material delaying the way a child develops mentally and physically.

The possessor of this genotype has the genetic disorder called Down syndrome. Down syndrome is caused by this person having chromosome 21, which is also called Trisomy 21. There are different things you see in people with Down syndrome such as, different physical and mental traits. This genetic condition varies between each person with this genetic disorder. They all have similar features, but do not look the same.

Down syndrome, also known as trisomy 21, is a genetic disorder caused by a third duplicate of chromosome 21. Down syndrome was first recognized as a distinct condition in 1866 by John Langdon Down, after whom the disease is named. Until 1970, the disorder was known as Mongolism and only recently become accepted as “down” syndrome. In 1959, French geneticist Professor Jerome Jejune discovered an extra chromosome to be the cause for the physical and intellectual abnormalities seen in individuals with DS. (Kazemi, Shojaei, & Sadighi, 2016). Down syndrome affects approximately one in every 1200 babies that are born, making it the most common genetic disorder. (Jobling, Virji- Babuls, & Nichols, 2006).

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