The purpose of this paper is the estimation of the interrelationship of molecular findings with clinical studies on Duchenne muscular dystrophy (DMD), the estimation of molecular genetic findings efficiency focused on the diagnosis and the prognosis and carrier detection in relatives with recommendation of prenatal diagnosis possibilities. DNA isolated from peripheral blood lymphocytes of 100 patients was examined. DNA analyses was performed by multiplex PCR for promoter and 21 exons of DMD gene in regions where mutations are most frequent. Deletions were detected in 55% of the cases. In cases with no deletions detected, PCR-SSCP and PCR-HD analysis were performed in order to detect point mutations. For selected introns and exon 48 the occurrence of the previously described polymorphism was confirmed. Mutation causing formation of shortened protein was detected in exon 6 of two patients. Point mutation analysis is important complement of molecular diagnostics of Duchenne muscular dystrophy in patients with no deletions. For each family at risk of DMD the analysis of mutant allele was performed and carrier status evaluated.