ABSTRACT
Non-progressive congenital myopathy is a group of muscle diseases occurring at birth or during teenage years. A number of new reports of congenital myopathy, such as homogeneous bodies myopathy, muscle quality control myopathy and type 1 fiber predominance have recently been reported, but they lack of sufficient quantity and constant clinico-pathologic manifestations. This paper reports two cases of congenital myopathy with type 1 fiber predominance confirmed by muscle biopsy. The clinical manifestations of the two children (a 4.5-year-old girl and an 11-year-old boy) included non-progressive symptoms of muscle weakness, skeletal deformities and other clinical features of congenital myopathy. The physical examinations showed a long face or figure and funnel chest or kyphosis/scoliosis, high palatal arch and wing-like shoulder. Serum levels of creatine kinase were normal but slightly elevated serum lactate dehydrogenase levels were noted in the two children. The skeletal muscle biopsy by ATPase staining showed that type 1 fibers accounted for more than 90% of the total number of muscle fibers. No other abnormal pathological changes, such as central cores, muscle tube and central nuclei, were found in the two children.
Subject(s)
Female , Humans , Infant , Male , Diagnosis, Differential , Muscle, Skeletal , Pathology , Myopathies, Structural, Congenital , Diagnosis , Pathology , TherapeuticsABSTRACT
<p><b>OBJECTIVE</b>to explore whether 6 tagging single nucleotide polymorphisms (SNPs) within SMAD4 gene were involved in the genetic susceptibility of coal worker's pneumoconiosis (CWP) by case-control study.</p><p><b>METHODS</b>this study consisted of 438 CWP patients and 448 controls. All study subjects were Han Chinese, underground coal miners and recruited from coal mines of Xuzhou Mining Business Group Co Ltd. The 5 ml venous blood sample was obtained from all studied subjects and extracted genome DNA from the isolated leucocytes. Six SNPs were selected from the HapMap and detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).</p><p><b>RESULTS</b>the single SNP analyses showed that the genotype frequencies of SMAD4 (rs10502913) was significantly different from those in controls (P < 0.05). Multivariate logistic regression analyses revealed that SMAD4 (rs10502913) AA genotype was associated with increased risk of CWP (adjusted OR = 1.63, 95%CI = 1.00 - 2.69, P = 0.05) and this was evident among subgroups of those smoker (adjusted OR = 2.28, 95%CI = 1.09 ∼ 4.80, P < 0.05) and cases with stage I (adjusted OR = 2.42, 95%CI = 1.41 ∼ 4.14, P < 0.01). The SMAD4 (rs9304407) GG genotype was associated with an decreased risk of CWP (adjusted OR = 0.65, 95%CI = 0.43 ∼ 0.98, P < 0.05) and the further stratification analysis showed that the risk of CWP was decreased in nonsmoking groups.</p><p><b>CONCLUSIONS</b>our results suggest that individuals with the SMAD4 (rs10502913) AA genotype was associated with an increased risk of CWP. However, carriers of SMAD4 (rs9304407) GG genotype have a protective effect on the developing CWP.</p>