Sunday, November 8, 2009

Downs Syndrome More Condition_symptoms Downs Syndrome?

Downs Syndrome? - downs syndrome more condition_symptoms

Hello, I need more information for my novel. Treatment of an abridged version of Down syndrome would be great, especially the later stages of the same, and experimental. If anyone knows where I may find something, or want to look up to sum up, I appreciate it.

1 comment:

Slick said...

What causes Down's syndrome



Down syndrome is usually caused by a defect in cell division called nondisjunction. However, two other types of chromosomal abnormalities, mosaic and translocation, are also in Down syndrome - although to a lesser extent. What kind of have Down syndrome can have a person, all people with Down's syndrome, a party critical of an extra chromosome number 21, in all or some of their cells. This additional genetic material changes over the course of development and causes the characteristics of the syndrome.


Nondisjunction

Nondisjunction is a faulty cell division that results in an embryo with three number 21 chromosomes instead of two. Before or design, a pair of chromosomes No. 21 is either not in the sperm or the egg separate, too. That the embryo develops, the extra chromosome repeated in every cell of the body. This faulty cell division is for 95 percent of all cases of Down syndrome responsible.

Why does non-disjunctionIs currently unknown, but appears to advanced maternal age is possible. Many people are surprised that 80 percent of children born with Down syndrome born to women under 35 years. This is because young women have the fertility rates. It contradicts the fact that the incidence is increasing of the births of children with Down syndrome with maternal age.

While there may be a non-disjunction of the paternal origin, this occurs less frequently. Present result of that error in cell division is usually the egg before conception, and women are born with a tent full of eggs, has been postulated that environmental factors may be associated with nondisjunction. Despite years of research, the cause of causes (o) of non-disjunction is still unknown. There seems no connection between any type of Down syndrome and the activities of their parents before or during pregnancy.


Mosaics

Mosaicism occurs when nondisjunction of chromosome 21 in a cell division after initial fertilization. If this happens, it is a mixture of two types of cells, some with 46 chromosomes and others with 47th These cells with 47 chromosomes contain an extra chromosome 21 Since the model of the "mosaic" of cells, uses the term mosaicism. Mosaic is rare, only one or two percent of all cases of Down syndrome.

Several studies have shown that people with Down syndrome were less than those affected with mosaic trisomy 21, but generalizations are not possible, as have the wide range of skills to people with Down syndrome.


Translocation

Translocation is another type of chromosomal problems, and comes only in three to four percent of people with Down syndrome. Translocation occurs when part of chromosome 21 is broken during cell division and attaches to another chromosome. While the total number of chromosomes in the cells remained constant at 46 years, the presence of an additional chromosome 21 in the number of cases, the characteristics of Down syndrome. As with nondisjunctioNo trisomy 21, translocation before or during the performance.

In contrast to non-disjunction is the age of the mother are not at risk in the context of resettlement. Most cases are sporadic, random events. In approximately one third of cases, one parent have a chromosomal translocation leads. For this reason, the risk of recurrence of the displacement is larger than the non-disjunction. Genetic counseling can be sought to determine the origin of the relocation.

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