Frameshift mutation in the collagen VI gene causes Ullrich's disease

Patients with Ullrich's disease have generalized muscle weakness, multiple contractures of the proximal joints, and hyperextensibility of the distal j oints. Recently, we found a deficiency of collagen VI protein in two patien ts with Ullrich's disease. In this study, we detected a homozygous 26 bp de letion in exon 14 of the collagen VI alpha 2 gene (COL6A2) in one patient. This mutation causes a frame-shift and a premature termination codon, and r esults in a truncated collagen VI alpha 2 chain. Our data suggest that at l east some cases of Ullrich's disease result from recessive mutations in COL 6A2.