PSSM Type 1 is associated with mutation in which gene?

PSSM Type 1 is associated with mutation in which gene?

• A. PKD1
• B. GYS1
• C. BRCA1
• D. MYH1

Answer: (B)

PSSM Type 1 is driven by a mutation in the gene that encodes glycogen synthase, GYS1. Glycogen synthase is the enzyme responsible for adding glucose units to form glycogen in muscle. When GYS1 is mutated, its activity or regulation is altered, causing excessive, abnormally structured glycogen-like material to accumulate within muscle fibers. This storage disrupts normal muscle function, leading to stiffness, exercise intolerance, and cramping after activity. The hallmark histology shows PAS-positive, diastase-resistant deposits in muscle fibers. The other genes listed are associated with different conditions (PKD1 with kidney disease, BRCA1 with cancer risk, MYH1 with other myopathies) and are not linked to PSSM Type 1.

PSSM Type 1 is driven by a mutation in the gene that encodes glycogen synthase, GYS1. Glycogen synthase is the enzyme responsible for adding glucose units to form glycogen in muscle. When GYS1 is mutated, its activity or regulation is altered, causing excessive, abnormally structured glycogen-like material to accumulate within muscle fibers. This storage disrupts normal muscle function, leading to stiffness, exercise intolerance, and cramping after activity. The hallmark histology shows PAS-positive, diastase-resistant deposits in muscle fibers. The other genes listed are associated with different conditions (PKD1 with kidney disease, BRCA1 with cancer risk, MYH1 with other myopathies) and are not linked to PSSM Type 1.