Becker Myotonia is a genetic condition that affects muscle function, characterized by delayed relaxation of muscles after contraction. It is caused by mutations in the CLCN1 gene, which is responsible for encoding a chloride channel in muscle cells. This condition is a type of myotonia, which can lead to stiffness and difficulty in muscle movement, particularly after periods of rest. Individuals with Becker Myotonia may experience symptoms such as muscle cramps and weakness, especially during physical activity. The severity of symptoms can vary widely among affected individuals. Diagnosis typically involves clinical evaluation and genetic testing to confirm the presence of mutations in the CLCN1 gene.