Polymerase chain reaction (PCR) was used to study the presence of gene deletion (the most prominent type of mutations) in some families afflicted by Duchenne muscular dystrophy/Becker muscular dystrophy (DMD/BMD). The results clearly demonstrate deletion in the central part of the DMD gene in two of the three families studied. This information can be useful for genetic counselling with particular reference to prenatal diagnosis and carrier analysis.