A radiographic, morphologic, biochemical and molecular analysis of a case of achondrogenesis type II resulting from substitution for a glycine residue (<tex>$Gly^{691}\rightarrow Arg$</tex>) in the type II collagen trimer
Faculty of Medicine and Health Sciences
Publication type
Oxford ,
Human medicine
Source (journal)
Human molecular genetics. - Oxford
4(1995) :2 , p. 285-288
Target language
English (eng)
Full text (Publishers DOI)
The type II collagenopathies form a continuous spectrum of clinical severity, ranging from lethal achond-rogenesis type II and hypochondrogenesis, through spondyloeplphyseal dysplasla, spondyloeplmetaphyseal dysplasia and Kniest dysplasia to the Stickler syndrome and famllial precocious osteoarthropathy at the mildest end of the spectrum. We have carried out a radiographic, morphologic, biochemical and molecular study In a case of achondrogenesis type II. Electron micrographs showed inclusion bodies of dilated rough endoplasmic reticulum in the chondrocytes and the presence of sparse collagen tibers in the cartilage matrix. Protein analysis of collagen from cartilage indicated posttranslational overmodlfication of the major cyanogen bromide peptides, and suggested a mutation near the carboxyl terminus of the type II collagen molecule. Analysis at the DNA level demonstrated that the phenotype was produced by a single base change (G→C) that resulted in the substitution of glycine691 by arginine in the type II collagen triple helical domain. We confirm previous observations in three cases of hypochondrogenesis that glycine substitutions in the α1(ll) chain can result in a phenotype at the most severe end of the type II collagenopathy spectrum.