Rett Syndrome is a rare and incurable disorder unknown to many people. According to the Encyclopaedia Britannica:"Rett syndrome [is a] rare progressive neurological disorder thatcauses mental retardation, compulsive hand movements, reducedmuscle tone, difficulties walking, autism, decreased body weight,failure of the head to grow with age, and the increased presence ofammonia in the blood." ("Brittannica" par 1)Rett syndrome primarily affects only females; however there are some cases where males are affected by this disorder. The reason Rett Syndrome (also called RTT or RS) mostly affects females is due to the fact that this disorder is commonly caused by a mutation of the methyl-CpG-binding protein 2, or MeCP2, gene. This gene is located on the X chromosome ("Overview" page 1 par 3). Females are born with two X chromosomes, while males are born with an X and a Y. When a female has RTT, she fortunately has another "back up" X chromosome, which can compensate for the other X chromosome and promote a more normal healthy life.
When males are diagnosed with RTT, they do not have another normal X chromosome. So if a male has RTT, he will usually not make it through childbirth ("Overview" page 1 par 3-4).
Rett Syndrome is a very rare disorder, so not many people know the symptoms. This is one of the reasons why this disorder is commonly misdiagnosed for autism and cerebral palsy ("Overview" page 1 par 2). According to Dr. Susan Walker-Date, "Although the condition is present from birth, new-born babies appear normal and seem to develop normally until the second year of life" (page 1 par 3). There are extensive tests that a child must go through before getting diagnosed. They range from genetic testings to mutation screenings (Williamson and Christodoulou page 1 fig. 1).