[Prenatal diagnosis of myotonic dystrophy: the first experience in Spain].

We report the first prenatal diagnosis of myotonic dystrophy (MD) in Spain by DNA techniques. The previous familiar study allowed us to determine the DM haplotype in this family with the following probe/enzyme combinations: p4.1/Msp I, LDR 152/Bgl II, Apo CII/Ban I, Taq I, Bam HI, pSCII/Bgl I. In the tenth week of amenorrhea, a transabdominal biopsy was done to obtain chorionic villi. One part of the sample was processed for the cytogenetic analysis that revealed a 46 XY karyotype. The other part was used to perform the molecular analysis with two probes, p4.1 and LDR 152, determining that the fetus was a DM gene carrier with a 96% probability.