Early myopathy fatal cardiomyopathy (Early-onset myopathy With fatal cardiomyopathy) - Gen TTN  

Early - onset myopathy with fatal cardiomyopathy (EOMFC), also known as dystrophy or congenital muscular dystrophy Salih Salih, is a hereditary muscular disease that affects skeletal muscle and cardiac muscle.

Skeletal muscle weakness becomes evident in early childhood, so affected individuals show a delayed development of motor skills. From childhood, people with EOMFC can also develop contractures that restrict movement of the neck and back. Scoliosis, also it develops in late childhood.

Dilated cardiomyopathy, another feature of the EOMFC, enlarges and weakens the heart muscle, which prevents the heart to pump blood efficiently. Signs and symptoms of dilated cardiomyopathy may include arrhythmia, shortness of breath, extreme fatigue and swelling of the legs and feet. Cardiac abnormalities associated with EOMFC usually do not appear in childhood. Heart disease gets worse quickly, often leading to heart failure and sudden death in adolescence or early adulthood.

Early myopathy fatal cardiomyopathy is due to changes in gene TTN (Titin), located on the long arm of chromosome 2 (2q31). This gene encodes titin protein, which plays a major role in skeletal and cardiac muscles. Within muscle cells, titin is an essential component of the sarcomeres. Sarcomeres consist of proteins that generate the necessary mechanical strength for the muscles to contract. Titin protein has several functions within the sarcomeres. One of its most important tasks is to provide structure, flexibility and stability to these cellular structures. In addition, it also plays a role in chemical signaling and assembly of new sarcomeres.

They have identified at least two mutations in the TTN gene in people with early - onset myopathy with fatal cardiomyopathy (EOMFC). These genetic changes occur near the end of TTN gene and result in the synthesis of an abnormally short version of titin protein. The defective protein alters the function of the sarcomeres, preventing the skeletal and cardiac muscle can develop and function normally. These muscle abnormalities underlying characteristic features of the EOMFC, including skeletal muscle weakness and dilated cardiomyopathy.

This disease is inherited in an autosomal recessive pattern, which means that both copies of the gene in every cell must have mutations for alteration is expressed. The parents of an individual with an autosomal recessive disease have a copy of the mutated gene, but usually show no signs and symptoms of the disease.  

Tests in IVAMI: in IVAMI perform detection of mutations associated with early myopathy fatal cardiomyopathy (EOMFC), by complete PCR amplification of the exons of the gene TTN, and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).