Characterization of a Blood Spot Creatine Kinase Skeletal Muscle Isoform Immunoassay for High-Throughput Newborn Screening of Duchenne Muscular Dystrophy

摘要

BACKGROUND: Duchenne muscular dystrophy (DMD) is a progressive, lethal X-linked neuromuscular disorder with an average worldwide incidence of 1:5000. Blood spot creatine kinase (CK) enzyme assays previously used in newborn screening programs for DMD are nonspecific because measured CK enzyme activity is attributable to 3 isoenzyme forms of CK (CK-MM, CK-MB, and CK-BB) and it is the CK-MM isoform that is found predominantly in skeletal muscle. CK-MM is increased in boys with DMD owing to muscle damage. We describe a sensitive and specific automated immunoassay for CK-MM to screen for DMD in blood spots.