Retts Syndrome Paper Essay Example

Retts Syndrome Paper Essay Example Retts Syndrome Paper Essay Retts Syndrome Paper Essay What is Rett syndrome? Retts syndrome is a neurodevelopmenal disorder that for the most part only affects women. Infants with Rett syndrome seem to grow and develop normally at first, but then stop developing and even lose skills and abilities. Retts Syndrome can be summed up by normal early growth and development followed by a slowing of development, loss of purposeful use of the hands, distinctive hand movements, slowed brain and head growth, problems with walking, seizures, and intellectual disability.The sickness was first breached upon by Dr. Andreas Rett who briefly described the illness and some of the occurring symptoms, and then later on Swedish researcher Dr. Bengt Hagberg published an article in 1883 giving a more detailed account of the disease. This stage is often overlooked because symptoms of the disorder may be somewhat vague, and parents and doctors may not notice the subtle slowing of development at first. The infant may begin to show less eye contact and have reduced interest in toys.Delays in the childs crawling or any type of movement becomes present. Hand-wringing and decreasing head growth may occur to subtle extents. This stage usually lasts for a few months but can continue for more than a year. Scientists generally describe four stages of Rett syndrome. Stage I, called early onset, typically begins between 6 and 18 months of age. This stage is often overlooked because symptoms of the disorder may be somewhat vague, and parents and doctors may not notice the subtle slowing of development at first.The infant may begin to show less eye contact and have reduced interest in toys. There may be delays in gross motor skills such as sitting or crawling. Hand-wringing and decreasing head growth may occur, but not enough to draw attention. This stage usually lasts for a few months but can continue for more than a year. Stage II, or the rapid destructive stage, usually begins between ages 1 and 4 and may last for weeks or months. Its onset may be rapid or gradual as the child loses purposeful hand skills and spoken language.Characteristic hand movements such as wringing, washing, clapping, or tapping, as well as repeatedly moving the hands to the mouth often begin during this stage. The child may hold the hands clasped behind the back or held at the sides, with random touching, grasping, and releasing. The movements continue while the child is awake but disappear during sleep. Breathing irregularities such as episodes of apnea and hyperventilation may occur, although breathing usually improves during sleep. Some girls also display autistic-like symptoms such as loss of social interaction and communication.Walking may be unsteady and initiating motor movements can be difficult. Slowed head growth is usually noticed during this stage. Stage III, or the plateau or pseudo-stationary stage, usually begins between ages 2 and 10 and can last for years. Apraxia, motor problems, and seizures are prominent during this stage. However, there may be improvement in behavior, with less irritability, crying, and autistic-like features. A girl in stage III may show more interest in her surroundings and her alertness, attention span, and communication skills may improve.Many girls remain in this stage for most of their lives. Stage IV, or the late motor deterioration stage, can last for years or decades. Prominent features include reduced mobility, curvature of the spine (scoliosis) and muscle weakness, rigidity, spasticity, and increased muscle tone with abnormal posturing of an arm, leg, or top part of the body. Girls who were previously able to walk may stop walking. Cognition, communication, or hand skills generally do not decline in stage IV. Repetitive hand movements may decrease and eye gaze usually improves.Nearly all cases of Rett syndrome are caused by a mutation in the methyl CpG binding protein 2, or MECP2 (pronounced meck-pea-two) gene. Scientists identified the gene - which is believed to control the functions of many other genes - in 1999. The MECP2 gene contains instructions for the synthesis of a protein called methyl cytosine binding protein 2 (MeCP2), which is needed for brain development and acts as one of the many biochemical switches that can either increase gene expression tell ot her genes when to turn off and stop producing their own unique proteins.Because the MECP2 gene does not function properly in individuals with Rett syndrome, insufficient amounts or structurally abnormal forms of the protein are produced and can cause other genes to be abnormally expressed. Not everyone who has an MECP2 mutation has Rett syndrome. Scientists have identified mutations in the CDKL5 and FOXG1 genes in individuals who have atypical or congenital Rett syndrome, but they are still learning how those mutations work. Scientists believe the remaining ases may be caused by partial gene deletions, mutations in other parts of the gene, or additional genes that have not yet been identified, and they continue to look for other causes. Rett syndrome is estimated to affect one in every 10,000 to 15,000 live female births and in all racial and ethnic groups worldwide. Prenatal testing is available for families with an affected daughter who has an identified MECP2 mutation. Since the disorder occurs spontaneously in most affected individuals, however, the risk of a family having a second child with the disorder is less than 1 percent.Genetic testing is also available for sisters of girls with Rett syndrome who have an identified MECP2 mutation to determine if they are asymptomatic carriers of the disorder, which is an extremely rare possibility. The MECP2 gene is found on a person’s X chromosome, one of the two sex chromosomes. Girls have two X chromosomes, but only one is active in any given cell. This means that in a girl with Rett syndrome only a portion of the cells in the nervous system will use the defective gene. Some of the childs brain cells use the healthy gene and express normal amounts of the protein.The severity of Rett syndrome in girls is in part a function of the percentage of their cells that carry a normal copy of the MECP2 gene. If the active X chromosome that is carrying the defective gene is turned off in a large proportion of cells, the symptoms will be mild, but if a larger percentage of cells have the X chromosome with the normal MECP2 gene turned off, onset of the disorder may occur earlier and the symptoms may be more severe. The story is different for boys who have a MECP2 mutation known to cause Rett syndrome in girls.Because boys have only one X chromosome (and one Y chromosome) they lack a back-up copy that could compensate for the defective one, and they have no protection from the harmful effects of the disorder. Boys with such a defect frequently do not show clinical features of Rett syndrome but experience severe problems when they are first born and die shortly after birth. A very small number of boys may have a different mutation in the MECP2 gene or a sporadic mutation after conception that can cause some degree of intellectual disability and developmental problems.