MYH7

File:A-de-novo-germline-mutation-in-MYH7-causes-a-progressive-dominant-myopathy-in-pigs-1471-2156-13-99-S1.ogv MYH7 is a gene that encodes for the beta myosin heavy chain protein, which is primarily found in the cardiac muscle and, to a lesser extent, in skeletal muscle. This protein plays a crucial role in the muscle contraction mechanism of the heart and skeletal muscles. Mutations in the MYH7 gene are associated with several cardiomyopathies and muscle disorders, making it a significant focus of medical research.

Function

The MYH7 gene produces the beta myosin heavy chain, a component of the thick filaments of sarcomeres, which are the fundamental units of muscle contraction. In the cardiac muscle, this protein is essential for the heart's pumping action, enabling blood to circulate throughout the body. In skeletal muscles, it contributes to the muscles' ability to generate force and movement.

Genetic Mutations and Associated Diseases

Mutations in the MYH7 gene can lead to a variety of muscle-related diseases. These include different forms of cardiomyopathy, such as hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM), which affect the heart's ability to pump blood effectively. Additionally, MYH7 mutations are linked to Laing distal myopathy and myosin storage myopathy, both of which are skeletal muscle disorders that impact muscle function and strength.

Hypertrophic Cardiomyopathy (HCM)

HCM is characterized by the thickening of the heart muscle, which can obstruct blood flow and lead to heart failure. Mutations in the MYH7 gene are one of the most common genetic causes of HCM. These mutations alter the normal function of the beta myosin heavy chain, leading to abnormal muscle growth and impaired heart function.

Dilated Cardiomyopathy (DCM)

In DCM, the heart's ventricles enlarge and weaken, reducing the heart's ability to pump blood. MYH7 mutations can disrupt the normal structure and function of the cardiac muscle, contributing to the development of DCM.

Skeletal Muscle Disorders

Mutations in the MYH7 gene can also cause skeletal muscle disorders, such as Laing distal myopathy and myosin storage myopathy. These conditions result in muscle weakness and atrophy, particularly affecting the distal muscles of the limbs.

Diagnosis and Treatment

Diagnosis of MYH7-related disorders typically involves genetic testing to identify mutations in the MYH7 gene, along with clinical assessments and imaging studies to evaluate muscle function and structure. Treatment options vary depending on the specific disorder and its severity but may include medications to manage symptoms, surgical interventions, and physical therapy to maintain muscle strength and function.

Research Directions

Ongoing research aims to better understand the molecular mechanisms by which MYH7 mutations lead to muscle disorders and to develop targeted therapies that can correct or mitigate the effects of these mutations. Advances in genetic engineering and molecular biology hold promise for the future management of MYH7-related conditions.