Bethlem Myopathy 2, also known as bthlm2, is related to ullrich congenital muscular dystrophy 2 and contractures, pterygia, and spondylocarpotarsal fusion syndrome 1a. An important gene associated with Bethlem Myopathy 2 is COL12A1 (Collagen Type XII Alpha 1 Chain). Affiliated tissues include skin and bone, and related phenotypes are flexion contracture and joint hypermobility