Effect of age on the detection rate in Duchenne muscular dystrophy.

In order to estimate SCK (serum creatine kinase) variability with age in carriers of Duchenne dystrophy (DMD), repeated SCK determinations in 10 obligate and 19 possible carriers were performed over a period of several years. Although there was some variation in some individuals, the differences in SCK means and risks of heterozygosity were not statistically significant between the first and second determinations. The present investigation indicates that the relation between SCK and age in carriers of the Duchenne gene is still controversial.