Objective To detect connexin32(Cx32) gene mutation in Charcot-Marie-Tooth disease(CMT) patients without CMT1A gene duplication.Methods Mutation analysis of Cx32 gene was performed by denaturing high-performance liquid chromatography(DHPLC) in combining with DNA pooling and DNA sequencing.The proband and 15 family members in a clinical possible X-linked dominant Charcot-Marie-Tooth disease(CMTX1) and 60 normal controls out of the family were studied.Three fragments including the whole coding region of Cx32 gene were amplified by polymerase chain reaction.Results Heteroduplex chromatogram was detected in fragment Ⅱ in proband by DHPLC and Leu89Pro(266T→C)missense mutation in exon 2 of Cx32 gene was proved by DNA sequencing.The same double peaks were detected in(4 patients) and 5 carriers,but not detected in normal controls.Conclusions Leu89Pro should be the pathogenic mutation in this family.Further study is needed to investigate the pathogenesis of the mutant.
Objective To study the routine methods that can be easily used in clinics to detect the Charcot Marie Tooth (CMT) disease gene duplication. Method Polymerase chain reaction(PCR) combined with restriction enzyme digestion and amplification of short tandem repeat (STR) sequence were used to detect gene duplication on chromosome 17p11.2～12 in 30 CMT1 patients and 10 CMT2 patients coming from unrelated families. 40 controls were also detected. Results 46.7%(14/30) of CMT1 patients were identified to have specific junction fragments. 53.3%(16/30)of them were identified as duplication by STR analysis. 70.0%(21/30) of CMT1 patients were identified to have gene duplication using both methods. Duplication was not identified in 10 unrelated CMT2 patients and 40 controls. Conclusion The PCR combined with restriction enzyme digestion represented a relatively sensitive and accurate method for detecting gene duplication in CMT1A cases for clinical diagnosis. The detecting rate of duplication can be increased using both restriction enzyme digestion of PCR products and STR methods.
Objective:To investigate the clinical data and brain MRI feature of 12 patients with hepatolenticular degeneration(HLD)as to offering evidences of early diagnosis and treatment.Methods:The clinical data and brain MRI feature of 12 patients diagnosed by the criteria of HLD were retrospectively analyzed.Results:The mean age at HLD onset was 23.5 years old.The first symptoms marked by extrapyramidal signs,by character changes and by academic achievement decline respectively are 10 cases,1 case and 1 case.Ceruloplasmin(CP)was below.Kayser-Fleischer ring was found in all the patients.MRI examination were found to have abnormal signal,symmetrically distributed in basal ganglia,thalamus,midbrain and pons.Conclusion:The clinical manifestations of HLD are variform.The measurement of CP,Kayser-Fleischer ring check and the MRI check have the important meaning to the diagnosis of HLD.
