TRIM32-related limb-girdle muscular dystrophy R8

TRIM32-related limb-girdle muscular dystrophy R8 (LGMDR8), formerly known as LGMD2H, is a rare autosomal recessive muscular dystrophy caused by pathogenic variants in the TRIM32 gene located on chromosome 9q33.1. The TRIM32 protein is an E3 ubiquitin ligase involved in protein degradation and cellular signaling pathways important for muscle maintenance. This condition primarily affects the skeletal muscular system, leading to progressive weakness and wasting of the proximal muscles, particularly those of the pelvic and shoulder girdles. Patients typically present with difficulty climbing stairs, rising from a seated position, and lifting the arms above the head. The onset of symptoms is variable but often occurs in late childhood, adolescence, or early adulthood. Disease progression is generally slow, and many patients remain ambulatory for decades. Facial muscles are usually spared. Serum creatine kinase (CK) levels are typically elevated. Some patients may also develop mild respiratory involvement over time. The condition was originally described in the Hutterite population of Manitoba, Canada, where it is more prevalent due to a founder effect. There is currently no cure or disease-specific treatment for LGMDR8. Management is supportive and multidisciplinary, including physical therapy to maintain mobility and prevent contractures, occupational therapy, orthopedic interventions as needed, and monitoring of respiratory and cardiac function. Genetic counseling is recommended for affected families. Research into gene therapy and other molecular approaches is ongoing but no targeted therapies have yet reached clinical use for this condition.

Common questions about TRIM32-related limb-girdle muscular dystrophy R8