PREIMPLANTATION DIAGNOSIS OF NONDELETION DUCHENNE MUSCULAR-DYSTROPHY (DMD) BY LINKAGE POLYMERASE-CHAIN-REACTION ANALYSIS

The use of preimplantation diagnosis for sex determination and detecti on of exon deletion means that unaffected babies can be born to parent s suffering from Duchenne muscular dystrophy (DMD). However, those who do not have exon deletion should also be considered for further inves tigation. A new method, known as linkage analysis, has been developed to diagnose the presence of non-deletion DMD in preimplantation embryo s. Linkage analysis uses informative intragenic and flanking markers t o track the chromosome bearing the mutated gene. The present study rep orts the analysis of two polymorphic sites, in blastomeres biopsied fr om embryos from a female carrier of DMD. A single male embryo was obta ined who had inherited alternate maternal alleles to the woman's affec ted surviving son, and this embryo was transferred.