Application of RFLP analysis to Duchenne and Becker muscular dystrophy in Shandong Province. I. Carrier detections in females at risk

There were eight intragenic and two flanking bridge DNA polymorphic markers used in the RFLP analysis in 21 Duchenne and Becker muscular dystrophy selected from nine different districts in Shandong Province. A total number of 173 individuals of the families were accepted for gene tracking and carrier detection, as well as prenatal diagnosis. Based on the frequency of the probe polymorphism tested in our study of 53 unrelated individuals, one to three high polymorphic probes were sequentially used and all families presented the informativeness in RFLP analysis. Some more introgenio probes were supplied for assessment of mutated sites and carrier status with the help of gene phases, if recombinations were found. Our results presented a ratio of 85.45% of carrier detection at risk females with 95% or more reliability, including 17 carriers and 30 non-carriers. It was not able to ascertain the carrier status of 8 females because of DNA absence from key family members. Finally, we proposed a diagnostic procedure for the RFLP analysis to DMD/BMD families.