Phenotype expression in women with CMT1X
Carly E Siskind1, Sinéad M Murphy, Richard Ovens
1Department of Neurology, Wayne State University, Detroit, MI 48201, USA. csiskind@med.wayne.edu
Journal of the Peripheral Nervous System : JPNS
|June 23, 2011
Summary
Charcot-Marie-Tooth disease type 1X (CMT1X) presents variable impairment in women. X-inactivation patterns in blood cells did not differ between CMT1X patients and controls, suggesting other factors influence disease severity.
Area of Science:
- Neurology
- Genetics
- Peripheral Neuropathy Research
Background:
- Charcot-Marie-Tooth disease type 1X (CMT1X) is a common inherited peripheral neuropathy.
- Women with CMT1X often exhibit milder symptoms than men, potentially due to X-inactivation.
Purpose of the Study:
- To characterize the clinical phenotype of women with CMT1X.
- To investigate if X-inactivation patterns in white blood cells (WBCs) differ between CMT1X females and controls.
Main Methods:
- Thirty-one women with CMT1X were assessed using the CMT neuropathy score (CMTNS) and CMT symptom score.
- X-inactivation patterns in WBCs were analyzed using the androgen receptor X-inactivation assay in 14 patients and 23 controls.
Main Results:
- Women with CMT1X showed variable impairment, with two-thirds having mild CMTNS and one-third having moderate CMTNS.
- No significant difference in X-inactivation patterns was observed between CMT1X patients and control groups.
- The study found no evidence that gap junction beta-1 (GJB1) mutations affect X-inactivation patterns in blood.
Conclusions:
- CMT1X phenotype in women is variable and not solely explained by X-inactivation patterns in blood.
- Further research is needed to elucidate the mechanisms behind the variable CMT1X phenotypes in females.
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