First described by Ullrich in 1930 and Bethlem in 1976, respectively . Caused by mutations in any of the 3 genes which code for collagen type VI synthesis, COL6A1, COL6A2 and COL6A3 . Collagen VI is a major contributor to the stability of the extracellular matrix. The remaining function of collagen VI determines the clinical severity of the disorder [3,4]. Considered different entities in the past, Bethlem and Ullrich myopathy are now considered extremes in the spectrum of collagen VI myopathy. Both inheritance (mostly autosomal recessive) and de-novo mutations (mostly autosomal dominant) are possible, the latter is more common. Combined prevalence is estimated at approximately 1 in 100,000 births (varying data for subtypes). Diagnosis relies on muscle biopsy and molecular genetic testing. There exists no causative treatment.