Biology 103

2001 First Web Report

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I decided to do Rett Syndrome for my Web Paper because it is a disease that has effected my family directly over the past seventeen years. It is also a very rare disease, and because of that it is not known by many people, so I figured I'd take this opportunity to enlighten you about it. Also while I am very familiar with the disease, there have been new gene developments over the past year or so that I do not know all about, but want to learn about. My seventeen year old sister has this disease. It is a neurological disorder most commonly found in girls. A girl that has Rett Syndrome will develop normally until about 18 months, and then, instead of gaining more skills, they begin to lose the ones they already have learned. My sister developed normally until she was 18 months. At that time, she could turn pages in books, she was starting to walk, she could feed herself. She was a very normal 18 month old baby. Right around that time her development came to a halt. She wasn't learning new things, and some of the things she knew how to do disappeared. My mom always describes my sister as being stuck at the age of 18 months. Being around girls with Rett Syndrome quite a bit, I think that is a great way of describing them.

Rett Syndrome randomly effects girls 1 in 10,000 girls. (8) There have been a few reported cases in males however males do not live past birth. Many girls have been misdiagnosed because Rett Syndrome is closely related to other disorders, such as autism, ataxic cerebral palsy, atypical Angelman's syndrome, mitochondria disease, spinocerebellar among others. (8) The reason that Rett syndrome is easily misdiagnosed, is because there is such a wide range in functioning among girls with Rett Syndrome. Rett Syndrome is diagnosed by the following: (8)

-Normal development until 6-18 months

-Normal head circumference at birth followed by slowing of head growth

-Loss of verbal language

-Purposeful hand use is replaced by stereotypical hand movements such as hand clapping, constant hand wringing, or other midline hand repetitive hand movement

-If able to walk the gait is usually wide-based and stiff legged

-Shakiness of torso and/or limbs, especially when upset

This criteria is used to diagnose girls with Rett Syndrome. There is a huge range in severity, which is what makes it so difficult to detect, and that is why it is so easy for it to be misdiagnosed. Here are some other symptoms that girls with Rett Syndrome may have: (8)

-Breathing Pattern Irregularities

-Seizures & EEG abnormalities

-Abnormal Sleep Patterns

-Digestive & Eating Difficulties

-Poor Circulation to Legs & Feet

-Decreased Body Fat & Muscle Mass

-Scoliosis & Kyphosis

-Severe Constipation

-Poor Nutrient Absorption & Reflux

-Decreased Mobility with Age

-Muscle Rigidity, Spasticity

-Tremors, Shaking, Jerking

-Growth Retardation

-Severe Teeth Grinding

-Severe Apraxia

As of right now scientists and doctors have not found a cure for Rett Syndrome, although everyday they are working toward that goal. Recent finding have instilled hope for a cure in the future….

Through many years of extensive research, scientists discovered the gene that causes Rett Syndrome. The gene is MeCP2 and it found on the far end of the X chromosome.(7) Scientists think that the function of MeCP2, is to be a gene silencer. Females have two X chromosomes, so for males and females to have the same amount of genes, females must silence one X chromosome in each of their cells. This is where the MeCP2 comes into play. Scientists think that girls with Rett Syndrome, have a defective MeCP2. The defect fails to silence the extra X chromosomes.(6) At this point this what scientist think about MeCP2, but there is still a lot to be learned about this gene.

There was a documentary made that tells about the disease and the huge new discoveries behind the genetics of Rett Syndrome. The documentary features a family of a girl with Rett Syndrome. The family decides that they want to have another child, but they are afraid because there is no way for them to know whether or not their next child will have Rett Syndrome. They find out that they are having a boy and they are relieved. They have their son, Ari, but there are huge complications at birth and Ari dies shortly after being born. Doctors study Ari and they realize that he had Rett Syndrome. But how can he have Rett Syndrome, when it only affects girls? This case, gave scientists and doctors huge clues about where the disease comes from. Ari had Rett Syndrome, but he was affected immediately after birth and he was killed by it. When a girl has Rett Syndrome it takes time for it to take effect and it is not deadly. Ari's case forced the doctors and scientists to examine the genetic differences between males and females and this was the clue they needed to start the process of locating Rett Syndrome in a physical way.

Ari's case helped answer some of the many questions scientists had been asking. Scientists thought that the disease occurred on the X chromosome and Ari's case proved that true. A male that is struck by Rett Syndrome cannot survive, because they only have one copy of the X chromosome.(7) One copy of the X chromosome contains a normal copy of the MeCP2 gene and the other copy contains the mutation of the gene. It is deadly in males because they don't have the normal copy of MeCP2 they only have the mutation of the gene.

While a cure is still undetermined, there is still hope to finding one in the future. Finding the gene was huge step toward the cure. It has opened the door for so many more things to be learned and discovered in the future. Right now, the finding of the gene will allow, women to find out if they are carriers of the disease, which is phenomenal development. Hopefully through more research the lives of the girls with Rett Syndrome will be made better, until one day, Rett Syndrome will be defeated.

WWW Sources

1)http://www.rettsyndrome.org/main/gene_Q_&_A.htm Gene Questions & Answers

2)Gene Today… Gone Tomorrow

3)http://www.hhmi.org/research/investigators/zoghbi.html In the Lab

4)International Rett Syndrome Association

5)http://www.rettsyndrome.org/main/interpret_mecp2results.htm Interpreting your MecP2 Analysis results

6)http://www.rsrf.org/MECP2.htmWhat Does MECP2 Do?

7)http://www.hhmi.org/news/zoghbi2.html News

8)http://www.rettsyndrome.net/whatisrett.html Rett Resources

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