Carrier detection and prenatal molecular diagnosis in a Duchenne muscular dystrophy family without any affected relative available

In this paper we report a family where the affected DMD patients were riot available for study and a molecular strategy was used for female carriers d etection and for prenatal diagnosis. Linkage analysis was performed with tw o markers within the DMD gene, in all family members screened. DMD markers used (pERT87.8/Taq1 and pERT87.15/Xmn1) seemed not to be informative becaus e the proposita's mother (II-2) was homozygous for the minor allele at each marker (T2 and X2), however, the proposita and one sister carried only the major allele, which was inherited from the father. These results suggested that a deletion involving both markers could be presents and was inherited from the mother to both daughters. Quantitative multiplex PCR confirmed th e deletion in female carriers, involving at least exons 12 to 17. DNA studi es of cultured amniotic fluid cells at 14 weeks gestation, by amplification of specific Y-chromosome sequences, followed by multiplex PCR, lead to the diagnosis of a male fetus affected by DMD. (C) 2001 Editions scientifiques et medicales Elsevier SAS.