Prenatal diagnosis of Duchenne muscular dystrophy by restriction fragment length polymorphism analysis with pERT 87 intragenomic deoxyribonucleic acid probes.

Prenatal diagnosis of DMD was performed with three intragenic genomic probes and chorionic villus sampling. A total of 8 unrelated families with at least one DMD were analysed. DNA was extracted from peripheral white blood cells for carrier testings (50 individuals). For prenatal detection, it was extracted from chorionic villi obtained by chorionic villus sampling at 9 menstrual weeks. DNA was digested with an appropriate restriction enzyme followed by overnight electrophoresis in 1% agarose gels. DNA was transferred from the gel to nylon membrane according to the protocol of an alkaline transfer method. The pERT 87 probes were labeled by nick translation. The membranes were hybridized overnight after prehybridization. After washing, the membranes were exposed to X-ray films to make autoradiograms for restriction fragment length polymorphism analysis. Fetal sex was determined by a rapid screening test with a Y chromosome-specific repeat sequence. Out of 8 fetuses, 4 were males and 4 were females. All of 4 male fetuses were determined to be unaffected. Out of 4 female fetuses, 3 were diagnosed as non-carriers, and the carrier status of the remaining one was not able to be determined because her mother was not informative for all testings.