Becker muscular dystrophy recombinant DNA studies in identical twins

Two identical twins with becker Muscular Dystrophy are reported. Both twins had the same red cell types for ABO, Rh, CDE, MNSs, Kelly, Lewis, Duffy, and Kidd. HLA typing detected the same antigens in both twins: A1, A26, B8, B17, DR3, DR7. Family history was negative. The twin patients showed identical haplotypes that were different from the haplotypes of the normal male members of the family. The sister of the twins showed a recombinant X chromosome. The informative haplotype with respect to the gene of BMD, present in the twins, was ascertained in their mother as well. Our findings strongly suggest that a mutation has occurred either in the mother or in the twins.