Clinical features of patients with Becker muscular dystrophy and deletions of the rod domain of dystrophin gene / 中华医学遗传学杂志

OBJECTIVE To explore the clinical features of patients carrying deletions of the rod domain of the dystrophin gene. METHODS Clinical data of 12 Chinese patients with Becker muscular dystrophy (BMD) and such deletions was reviewed. RESULTS Most patients complained of muscle weakness of lower limbs. Two patients had muscle cramps, one had increased creatine kinase (CK) level, and one had dilated cardiomyopathy. CONCLUSION Compared with DMD, the clinical features of BMD are much more variable, particularly for those carrying deletions of the rod domain of the dystrophin gene. Muscular weakness may not be the sole complaint of BMD. The diagnosis of BMD cannot be excluded by moderately elevated CK. For male patients with dilated cardiomyopathy, the possibility of BMD should be considered.

Analysis of SMN1 gene mutations in 78 patients with spinal muscular atrophy / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the significance of SMN1 gene mutations among patients with spinal muscular atrophy (SMA) and the value of multiplex ligation dependent probe amplification (MLPA) for its diagnosis.</p><p><b>METHODS</b>Potential mutations of the SMN1 gene were detected among 78 SMA patients with a MLPA assay.</p><p><b>RESULTS</b>Homozygous deletion of SMN1 exons 7 and 8 was detected in 70 (89.7%) of all patients. Homozygous deletion of exons 7 and heterozygous deletion of exon 8 was detected in 3 patients (3.8%). Homozygous deletion of SMN1 exons 7 alone was detected in 3 patients (3.8%). Heterozygous deletion of SMN1 exons 7 and 8 was detected in 2 patients (2.6%). For 77 of the patients, both parents were found to carry heterozygous deletion of the SMN1 gene, which was consistent with the recessive inheritance of SMA. One patient with SMA type I was found to be rather rare. The patient was found to carry homozygous deletion of SMN1 exons 7 and 8, for which her mother was heterozygous, while no mutation was found in her father.</p><p><b>CONCLUSION</b>Homozygous deletion of the SMN1 gene have been detected in more than 95% of SMA patients. No homozygous deletion of exon 8 has been found. Homozygous deletion of exon 7 is more significant in the pathogenesis of SMA.</p>

Long-term follow up of four patients with dopa-responsive dystonia / 中华神经科杂志

Objective To investigate the clinical characteristics,treatment effect,long-term follow up results,guanosine triphosphate (GTP) cyrclohydrolase Ⅰ (GCH Ⅰ)gene and tyrosine hydroxylase(TH) gene mutations in patients with dopa-responsive dystonia (DRD).Methods The clinical features of 3 families with 4 affected members were analyzed and all of 4 patients were screened for mutations of the GCH Ⅰ gene and TH gene with DNA sequences.Results Four patients were females,average age at onset was (15.3 ± 5.6) years (range:from 9 to 20 years).The initial symptoms were a gait disorder,stiffness or tremor of the lower limbs in all patients presented with diurnal fluctuation.As the increase of disease duration,bilateral hand tremor was found in three patients,systemic torsion was found in one patient and torticollis was found in one patient.All patients' symptoms were in complete remission after administration of low dose of levodopa.Four patients were followed up for 0.5 to 10.0 years,and all were still responsive to the levodopa treatment and effective dosage was decreased as the increase of the disease duration.No longterm side effects of levodopa had occurred after long-term treatment.One patient was found to have c.607G ＞A(p,Gly203Arg) heterogenetic mutation in GCH I gene.Molecular analysis revealed a compound heterozygous mutation in the TH gene (p.Y447Ter and p.V468M) in one patient.No point mutations in both genes were found in other patients.Conclusions DRD patients have dramatic and sustained response to levodopa and no long-term side effects of levodopa after long-term treatment.The detection of GCH Ⅰ and TH gene mutations is helpful in early diagnosis but the negative results could not exclude the diagnosis of DRD.

Clinical characteristics of adult-onset type Ⅱ citrullinemia: one case report / 中华神经科杂志

Objective To enhance clinicians' intention to the importance of early diagnosis,early therapy and follow-up of type Ⅱ citrullinemia.Methods The clinical data of one adult-onset type Ⅱ citrullinemia pedigree were collected. The gene mutation type of SLC25A13 of proband and her daughter were determined by PCR and direct gene sequencing.Results The patient was a 27 years-old female,who complained of repeated dizziness, vomiting for more than 2 years and recurrent attacks of altered consciousness for about one and a half year.An abdominal ultrasonogram,liver magnetic resonance imaging and liver histology obtained by needle biopsy all determined the liver pathological changes of liver cirrhosis.Electroencephalogram showed sharp waves. The plasma amino acid showed a marked elevation of blood citrulline.Laboratory findings revealed a highly increased concentration of plasma ammonia during every episode. Mutation analysis of the SLC25A13 gene identified a homozygote of 851del4 in the patient,and heterozygote of 851del4 in her daughter. Conclusions For adults,unexplained dizziness,vomiting,but liver function still in the compensation,especially accompanied by neuropsychologic symptoms are highly suggestive of adult-onset type Ⅱ citrullinemia.SLC25A13 gene analysis contributes to the diagnosis of this disease,avoids invasive investigations and early confirmation of this disease means long-term dietary advice,genetic counseling,medical surveillance and early preparation for liver transplantation if is necessary.

Clinical, familial and hereditary analysis of myotonic dystrophy / 中南大学学报(医学版)

OBJECTIVE@#To analyze the clinical, familial and hereditary features of myotonic dystrophy to improve the knowledge and provide molecule evidence for gene diagnosis and prenatal diagnosis of myotonic dystrophy or dystrophia myotonia (DM) families.@*METHODS@#Clinical data of 2 DM families were collected based on the probands. The number of trinucleotide CTG repeat in the 3' untranslated region of myotonic dystrophy protein kinase (DMPK) gene on chromosome 19 was determined by DNA sequence and repeat fragment.@*RESULTS@#Except for 1 subclinical patient, another 5 patients progressed slowly with the features of myotonic muscular weakness and atrophy. One patient had hatchet face, 1 had cataract and diabetes mellitus, and the other 3 were bald. Electromyologram showed 3 patients had myotonic discharge and myopathic abnormalities. The number of trinucleotide CTG repeat in the 3' untranslated region of DMPK gene of 5 patients exceeded 50.@*CONCLUSION@#DM can be anticipated. Gene analysis can verify the disease and identify subclinical patients. It helps to prevent the DM births by hereditary consultation performing prenatal diagnosis.