Chelsea's Rett mutation

[Guest guest]

Well, we finally saw her local neuro yesterday, and I got a copy of the MeCP2 sequence analysis results. It was done at the U of Chicago genetic services lab. For anyone interested, here is exactly what the report said:

Results: Abnormal

R168X mutation present in the MeCP2 gene.

Coding exons 2, 3, and 4 of the MeCP2 gene were PCR amplified and cycle sequenced in both forward and reverse directions from genetic DNA isolated from the patient's blood sample. A 502C[arrow]T(R168X) mutation, was detected in exon 4 of the MeCP2 gene in this patient.

Interpretation:

DNA sequence analysis of the MeCP2 gene in this patient demonstrated a base pair change that results in the premature stop codon at amino acid 168. this mutation is predicted to result in a truncated protein and is likely the cause of this patient's phenotype. This mutation has previously been described in other patients with Rett Syndrome (sources cited)

It is possible the patient's mother carries this mutation but is clinically unaffected due to favorable X-inactivation. In addition, germiline mosaicism for MeCp2 mutations has previosly been observed. The risk to future pregnancies may be as high as 50%, depending on the carrier status of the mother. Mutation analysis and prenatal diagnosis is available for this patient's family members who may be at risk for carrying the mutation or having an affected child. Genetic counseling is recommended.

Our interpretation is based on the current understanding of the genetics of Rett Syndrome.

So, from what I understand her specific mutation is R168X on exon 4 of the X chromosome. Does anyone know what amino acid 168 is? Or where I can find out?

(For the reattangels list)I am also curious about me being a possible carrier. From what I have read about RS, the chance of heredity less than 1%. Are there any specific mutations that are associated with family heredity? We will be referred to a local geneticist. The only problem is, Chelsea is on medicaid, and I have no ins. I doubt her medicaid will pay to have me tested. I am sure this testing will be very expensive, so I am not sure what will happen as far as that goes.

It is finally nice to have something in writing that confirms her diagnosis. As far as possible mitochondrial issues, either primary or 2ndary, her neuro hadn't heard of it with RS, but was going to research into it. Hopefully that will be confirmed one way or the other as well. As far as her supplements and meds, there will be no change, except increasing the Lamictal. If ther are any ?'s, please feel free to ask.

e, Chelsea's mom, 7, Atypical RS (FKA nonspecific mito)