The Pathogenesis of Down’s Syndrome

Down syndrome etiology Down syndrome (DS) is the most common cause of mental retardation in the United States. It happens in one of 700 births. Due to chromosomal variation (95% non-isolated, 5% translocation), the presence of 21 copies of chromosome 3 during cell division results in disease leading to total chromosome 47 instead of normal number. Individuals with clinical symptoms of DS, but not at least chromosome 21 trisomy.

In Down's syndrome Down's syndrome, one is born with an extra copy of chromosome 21, one of 23 chromosomes. Scientists do not know why Down Syndrome is at high risk of Alzheimer's disease, but it may be associated with extra copies of chromosome 21. This chromosome contains the gene encoding APP, which is excised into beta-amyloid fragment in Alzheimer's disease and accumulates in plaques. Extra copies of chromosome 21 increase the number of beta-amyloid fragments in the brain

Three copies of Down's syndrome of karyotype 21 chromosome of trisomy down syndrome are based on too many copies of chromosome 21. Generally, this leads to overexpression of genes. Understanding the genes involved may help in treating people with Down's syndrome. It is estimated that chromosome 21 contains 200 to 250 genes. Recent studies identified chromosomal regions containing key genes that contribute to the pathogenesis of Down's syndrome. Additional chromosomal material may appear in several different ways. A typical human karyotype is designated 46, XX or 46, XY, representing 46 chromosomes with typical female XX sequences and 46 chromosomes with typical male XY sequences. 1 to 2% of the observed Down's syndrome. Several cells in the body are normal, the other cells have 21 trisomy. This is called Mosaic Down Syndrome (46, XX / 47, XX, + 21). Trisomy 21

Cruber - Bashy syndrome - Behavioral disorder that occurs when the right medial temporal lobe and the medial temporal lobe of the brain stop functioning. Amygdala is the brain area that is particularly involved in the pathogenesis of this syndrome. Cruber - Bashy syndrome causes individuals to put things in their mouths or cause inappropriate sexual behavior. Other symptoms include visual helplessness (visually unable to identify objects), normal fear and loss of anger, loss of memory, distraction, seizures, dementia, and the like. This disease may lead to brain injury may be associated with herpes encephalitis and trauma