Chromosome+20

=__ADA Gene__=



What's the function of Adenosine Deaminase?

 * the enzyme develops lymphoid tissues
 * lymphoid tissues forms the immune system, which fights off foreign and harmful invaders.
 * ADA gets rid deoxyadenosine (an enzyme that is developed when DNA is broken down.) Ada converts the harmful enzyme into another non-harmful one, deoxynosine, because deoxyadenosine is harmful to lymphocytes.

Why is the damage of lymphocytes so crucial?

 * lymphocytes is very important.They are apart of the immune system - involved in defending the body against both infectious diseases. It comes from from a cell in the bone marrow.

According to Genetics Home Refernce (2011): Adenosine deaminase deficiency - caused by mutations in the ADA gene More than 70 mutations in the ADA gene have been identified. Most of these mutations result in the substitution of one protein building block (amino acid) for another amino acid in the adenosine deaminase enzyme. Other mutations cause the enzyme to be unstable or prevent it from being produced at all.These mutations result in the absence or deficiency of the adenosine deaminase enzyme in cells, preventing the normal breakdown of deoxyadenosine. A buildup of this toxic compound interferes with the development and maintenance of lymphocytes, resulting in severe combined immunodeficiency (SCID), which is characteristic of adenosine deaminase deficiency."

=__EDN3 Gene__= Official name: endothelin 3

What is the function of EDN3 gene

 * its responsible for creating instructions for endothelin 3.
 * they help the development and function of blood vessels.
 * responsible for starting cell growth and division
 * produces certain hormones
 * functions by interacting with another protein
 * responsible for Hirschsprung disease in people without Waardenburg syndrome


 * ==Interacts with Endothelin Receptor B on th surface of cells==
 * both play a important roll in neural crest cells

- A condition that affects the normal development and function of the brain. A feature that could take place due to this condition is recurrent seizures (epilepsy) in childhood.( occurs during the day or while your asleep at night ) - This condition only affects the frontal lobe part of the brain. - Treated with anit-epileptic drugs. - People with this disease have some kind of intellectual disability and behavioral difficulties. Other features due to this condition would be : (facial features ) - slow growth - short statue -small head - A rare condition. - More than 60 of affected individuals have been reported for this medical disorder. -a circular structure. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; margin-left: 1.25in; text-align: left; text-decoration: none; text-indent: -0.25in;"><span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-decoration: none; vertical-align: auto;">- When a chromosome breaks in two places and its broken ends fuse together. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; margin-left: 1.25in; text-align: left; text-decoration: none; text-indent: -0.25in;"><span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-decoration: none; vertical-align: auto;">- People with ring chromosome 20 syndrome have one copy of this abnormal disease in some or all of their cells. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; margin-left: 1.25in; text-align: left; text-decoration: none; text-indent: -0.25in;"><span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-decoration: none; vertical-align: auto;">- Genes near the end of chromosome 20 are deleted when the ring chromosome forms. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; margin-left: 1.25in; text-align: left; text-decoration: none; text-indent: -0.25in;"><span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-decoration: none; vertical-align: auto;">- Researchers suspect that the loss of these genes may be responsible for epilepsy and other health problems. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">**<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">__<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 19px; line-height: 115%; text-align: left; vertical-align: auto;">__(Chromosome 20 )RC20:__ __ ** <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none; text-indent: -0.25in;"><span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-decoration: none; vertical-align: auto;">- **<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">WWhat is RC20? ** <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; margin-left: 1in; text-align: left; text-decoration: none;">*Is one of a number of chromosomal disorders associated with refractory epilepsy. A ring chromosome is formed by the fusion of two arms of a chromosome during prenatal development. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">- **<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">When does it occur? ** <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">*between day one of postnatal life to 17 years <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">- **<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">What is this syndrome characterized with ? ** <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">*characterized by behavioral problems, mild mental retardation, cognitive impairment and learning disabilities. Epilepsy appears to be the first and major clinical symptom of this syndrome, its seen as a constant feature, and is often drug resistant. Seizures associated with RC20 syndrome are often complex partial and are altered consciousness with staring, oral automatisms, unspecified automatic behavior, focal motor symptoms and/or head turning. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">- **<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">How is this syndrome diagnosed? ** <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">*Ring Chromosome 20 syndromes is diagnosed by representation of the features outlined above and through looking at the pattern of chromosomes in the affected person’s cells. This is most easily done by looking at the chromosome pattern in blood cells but any other tissue including skin could be examined, karyotype. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">- **<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">Is Epilepsy present in all individuals? ** <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">* No,epilepsy is not present in all individuals with RC20, although, it is the most consistent clinical feature. Unlike other chromosomal disorders with epilepsy, are rarely a part of this condition. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">- **<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">How common is this ? ** <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">* It’s a rare condition that has been reported in the medical literature for further studies. Also some people with difficult-to-control epilepsy may have a ring chromosome 20 but are not aware of it. <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">- **<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">How to treat this syndrome? ** <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">* Seizures with RC20 are very difficult to treat. Every situation in a person is different and complex. Antiepileptic drugs are the main and first line of treatment, although no one drug or treatment has been shown to be better than others. Patients are frequently exposed to multiple antiepileptic drugs. Epilepsy in RC20 cannot have surgery done because of the lack of focal epileptogenic region
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">**<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">__<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 21px; line-height: 115%; text-align: left; vertical-align: auto;">__Ring chromosome 20 syndrome:__ __ **
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">**<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">How common is ring chromosome 20 syndrome: **
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">**<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">Physical structure: **
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">**<span style="background-color: transparent; color: #000000; font-family: Times New Roman; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">When it happens : **

<span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">__<span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 27px; text-align: left;">__Facts:__ __ <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;"> <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">__<span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 24px; text-align: left;">__Quote from the Book:__ __ <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;"><span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-decoration: none; vertical-align: auto;">“On chromosome 20 there lies as <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;"><span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-decoration: none; vertical-align: auto;">irritating and fascinating a copse of mystery as any.” <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;">__<span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 24px; text-align: left;">__Citations:__ __
 * <span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 16px; text-align: left; text-decoration: none;">Chromosome 20 likely contains between 700 and 800 genes.
 * <span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 16px; text-align: left; text-decoration: none;">Many genetic conditions are related to changes in particular genes in chromosome 20.
 * <span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 16px; text-align: left; text-decoration: none;">7% people with Alagille syndrome have small deletions of genetic material on their chromosome 20, it can affect their heart, bile ducts in the liver, the spinal column, and certain deadly features
 * <span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 16px; text-align: left; text-decoration: none;">Chromosome 20 can also provoke several types of cancers.
 * <span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 16px; text-align: left; text-decoration: none;">Deletions involving in chromosome 20 appear to be common in blood-related cancers such as leukemia and lymphoma. It can also relate to bone marrow, including polycythemia vera (overproduction of red blood cells) and myelodysplastic syndrome (lack of healthy blood cells).
 * <span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 16px; text-align: left; text-decoration: none;">A ring chromosome occurs when a chromosome breaks in two places and its broken ends fuse together. People with ring chromosome 20 syndrome have one copy of this abnormal chromosome in some or all of their cells; it can also make it unable to copy itself normally during cell division.
 * <span style="background-color: transparent; color: #000000; font-family: "Times New Roman",serif; font-size: 16px; text-align: left; text-decoration: none;">Deletions or duplications of genetic material from chromosome 20 can have a variety of effects, like disabilities in learning, development may delay, distinctive facial features, abnormal skeletal, and heart defects.
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;"><span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-decoration: none; vertical-align: auto;">Ring Chromosome 20 Syndrome | epilepsy.com. (n.d.). //<span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">Epilepsy and seizure information for patients and health professionals | epilepsy.com //. Retrieved May 24, 2011, from http://www.epilepsy.com/epilepsy/epilepsy_ringchromosome
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;"><span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-decoration: none; vertical-align: auto;">Ridley, M. (1999). //<span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">Genome: the autobiography of a species in 23 chapters //. New York: HarperCollins.
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;"><span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-decoration: none; vertical-align: auto;">Human Genome Project: Chromosome 20 - Wellcome Trust Sanger Institute. (n.d.). //<span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">Home page - Wellcome Trust Sanger Institute //. Retrieved May 24, 2011, from http://www.sanger.ac.uk/about/history/hgp/chr20.html
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;"><span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-decoration: none; vertical-align: auto;">Chromosome 20. (n.d.). //<span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">Genetics Home Reference //. Retrieved May 24, 2011, from ghr.nlm.nih.gov/chromosome/20
 * <span style="background-color: transparent; color: #000000; display: block; font-family: "Times New Roman"; font-size: 16px; text-align: left; text-decoration: none;"><span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-decoration: none; vertical-align: auto;">20. (n.d.). //<span style="background-color: transparent; color: #000000; font-family: 'Times New Roman','serif'; font-size: 16px; text-align: left; text-decoration: none; vertical-align: auto;">The Ring Chromosome 20 //. Retrieved May 24, 2011, from www.ring-chromosome-20.org