Carrier detection in Duchenne muscular dystrophy: Assessment of the effect of age on detection-rate with serum-creatine-kinase-activity.

In 40 known carriers of the gene for Duchenne muscular dystrophy (mean age 38 years) the detection-rate with a standard assay of serum-creatine-kinase was 53%. In 52 daughters of known carriers (mean age 16 years) the detection-rate was 45% after correction of age. This implies a much higher detection-rate (about 90%) in young carriers and suggests that discrimination between carriers and noncarriers may best be achieved by testing in childhood.