Rett syndrome is a childhood neurodevelopmental disorder that affects females almost exclusively. Loss of muscle tone is usually the first symptom. Other early symptoms may include problems crawling or walking and diminished eye contact. As the syndrome progresses, a child will lose purposeful use of her hands and the ability to speak. Compulsive hand movements such as wringing and washing follow the loss of functional use of the hands. The inability to perform motor functions is perhaps the most severely disabling feature of Rett syndrome, interfering with every body movement, including eye gaze and speech.
Genetically Rett syndrome is caused by mutations in the gene MECP2 located on the X chromosome. In at least 95% of cases, the mutation is a de novo event meaning it is not inherited from either parent. The MECP2 gene encodes the protein MECP2. MECP2 appears to be essential for the normal function of nerve cells. The protein seems to be particularly important for mature nerve cells, where it is present in high levels. The MECP2 protein is likely to be involved in silencing and activating several other genes. MECP2 protein is found in all cells in the body, including the brain, acting as a transcriptional repressor and activator, depending on the context. In the brain, it is found in high concentrations in neurons and is associated with maturation of the central nervous system (CNS) and in forming synaptic contacts.
DNA sequencing of the entire MECP2 coding region detects disease-causing mutations in approximately 80% of individuals with classic Rett syndrome.
Methodology: Sequencing analysis
Purpose: Confirmation of Clinical Diagnosis
ICD-10 Code F84.2
Test Requisition: Sequencing Requisition
CPT Codes: 81302 full gene sequence Cost: $863.00
CPT Code: 81303 known familial mutation Cost: $396.00
Turn-around-time: 21 days
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