Position of Glycine Substitutions in the Triple Helix of COL6A1, COL6A2, and COL6A3 is Correlated with Severity and Mode of Inheritance in Collagen VI Myopathies

摘要: Glycine substitutions in the conserved Gly-X-Y motif triple helical (TH) domain of collagen VI are most commonly identified mutations myopathies including Ullrich congenital muscular dystrophy, Bethlem myopathy, and intermediate (INT) phenotypes. We describe clinical genetic characteristics 97 individuals with glycine TH COL6A1, COL6A2, or COL6A3 add a review published cases, for total 194 cases. Clinical findings include severe, INT, mild phenotypes even from patients identical mutations. INT were common, accounting almost half patients, emphasizing importance to overall phenotypic spectrum. heavily clustered short segment N-terminal 17th triplet, where they acting as dominants. The severe cases an smaller region triplets 10-15, only 5% domain. Our suggest that clustering is not based on features primary sequence. hypothesize this may represent functional within helix.