Objective To identify the deletions in Duchenne/Becker muscular dystrophy (DMD/BMD) by using fluorescence in situ hybridization (FISH) Methods The exon-specific cosmid DNA probes (representing 18 exons) were used to perform one-color FISH on metaphase and interphase preparations. The peripheral blood samples from 9 normal people (4 males and 5 females) and 5 females from independent deletion DMD/BMD families, as well as 2 amniotic fluid specimens and 2 chorionic villus samples (CVS) from normal pregnant females were analyzed.Results 72%～100% of peripheral blood lymphocyte metaphases or interphases, 60%～70% of amniocyte interphases, and 95～99% of chorionic villus cell interphases showed expected signals. One suspected female was identified as deletion carriers and two were excluded.Conclusion FISH in combination with other available techniques allows efficient screening of DMD/BMD deletion carriers, which also lay the ground work for prenatal diagnosis for potential fetal carriers.