A novel MYH7 mutation resulting in Laing distal myopathy in a Chinese family

To the Editor:Distal myopathy is a heterogenetic disorder characterized by early distal lower limb involvement,which has been linked to 18 disease-causing genes.The gene responsible for Laing distal myopathy(LDM,also called distal myopathy 1;OMIM 160500)was determined to be the myosin heavy chain 7 gene(MYH7)located on chromosome 14q11.[1] MYH7 encodes the myosin heavy chain beta isoform(MyHC-β)and is expressed predominantly in the cardiac ventricle and in type 1 skeletal muscle fibers.