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Query: UMLS:C0019270 (hernia)
 15,856 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The features of a 32 year old woman with Ehlers-Danlos syndrome type VIIB and affected members of her family, resulting from a mutation in one COL1A2 allele, were studied. Her dermal type I collagen contained alpha 2(I) chains and mutant pN-alpha 2(I) chains in which the amino-terminal propeptide remained attached to the alpha 2(I) chain. She was heterozygous for an AG-->AC mutation at the splice acceptor site of intron 5 of the COL1A2 gene. The mutation activated a cryptic AG splice acceptor site corresponding to positions +14 and +15 of exon 6 of the COL1A2 gene. In contrast to previous reports only five, rather than all 18, amino acids encoded by exon 6 were deleted in the proband. The deleted peptide removed the amino-proteinase cleavage site, but not the nearby lysine cross linking site in the amino-telopeptide of the alpha 2(I) chain. She was born with bilateral hip dislocations, knee subluxations, and generalised joint hypermobility. Bilateral inguinal herniae and an umbilical hernia were present at birth. Facial features included a depressed nasal bridge with prominent paranasal folds. The skin was soft, moderately hyperelastic, and sagged over the face. Skin fragility and easy bruising were apparent from childhood. Skin wounds healed slowly and with broad, paper thin scars. Throughout her life, she had multiple fractures of the small bones of her hands and feet following moderate trauma. Electron microscopy of the proband's dermis as well as deep fascia and hip joint capsule from her affected brother showed that collagen fibrils in transverse section were nearly circular but with irregular margins. Light microscopy of bone from her affected brother and son showed normal Haversian systems and lamellar bone. All of these tissues contained approximately equal amounts of the normal and mutant alpha2(I) chains. The findings of this study confirm that loss of the amino-proteinase cleavage site of the pro alpha2(I) collagen chains, owing to anomalous splicing of exon 6 sequences in the conversion of pre-mRNA to mRNA, produces the clinical features of Ehlers-Danlos syndrome type VIIB. The history of frequent fractures found in this family is atypical and indicates an overlap with osteogenesis imperfecta.
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PMID:The clinical features of Ehlers-Danlos syndrome type VIIB resulting from a base substitution at the splice acceptor site of intron 5 of the COL1A2 gene. 807 56

Ehlers-Danlos syndrome (EDS) type VIIC is a newly recognized human disorder which results from failure to remove the amino-terminal propeptide of type I procollagen. Four cases of EDS type VIIC have been reported, and here we describe a fifth case. The propositus was a 1,445 g male infant born at 30 weeks of gestation following premature rupture of membranes. He had wide fontanelles, prominent eyes with swollen eyelids and blue sclerae, anteverted nostrils, micrognathia, umbilical hernia, short stubby fingers, and cutis laxa with hirsutism. At age 3 months, during the repair of the umbilical hernia, he was noted to have unusual skin fragility. Examination of skin by scanning electron microscopy showed frayed collagen fibrils, and transmission electron microscopy showed the hieroglyphic collagen fibril morphology characteristic of the disorder. As reported in other cases, cultured fibroblasts synthesized type I procollagen that was very poorly processed at the amino-terminal propeptide cleavage site. the 5 known cases of human EDS type VIIC characterize a distinct clinical phenotype, making this condition recognizable at birth before manifestation of severe skin fragility. The diagnosis can be confirmed by biochemical studies of type I procollagen synthesis and by electron microscopic examination of skin.
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PMID:Clinical, morphological, and biochemical phenotype of a new case of Ehlers-Danlos syndrome type VIIC. 898 71