Bethlem myopathy demonstrated in three generations of a rural West Virginia family carrying an autosomal dominant COL6A3 mutation

Mutations in the genes that code for type VI collagen can lead to what are known as the collagenopathies (collagen VI myopathies), such as Bethlem myopathy (BTHLM1), which affect structural tissues like muscles and tendons. We present the case of a young female and her two relatives, who were discovered to share the autosomal dominant COL6A3 mutation and whose presentation in clinic varied from mild to severe. Type VI collagenopathies represent a clinically and genetically heterogeneous spectrum of disorders generally characterized by muscle weakness and joint contractures. We highlight the importance of examining close relatives whenever possible and documenting a pedigree prior to proceeding with further electromyography (EMG) and lab work up, which includes obtaining genetic testing in order to reach a unifying diagnosis. The proband (L.C.) reported challenges with activities of daily living due to distal hand weakness, had significant findings on neuromuscular exam, and had abnormalities on needle EMG testing. Five of her relatives were reported to have weakness and trouble with day-to-day function. Her mother (M.C.) and her maternal grandfather (W.C.) were able to be examined in person and had the condition genetically confirmed