Shared decision making remains a challenge. A sustained training effect may require more intensive training tailored to the local setting. Cross-cultural differences need attention in conducting trials on communication interventions.

Targeted professional attention to this high-risk cohort of young women is critical to inform the next generation of daughters of BRCA1/2 mutation carriers and encourage recommended screening by age 25 years. Improved uptake of screening and risk reduction options could improve survival, and psychoeducation could reduce cancer-related distress.

The Duchenne muscular dystrophy (DMD) locus has been localized to the short arm of the human X chromosome (Xp21) by detection of structural abnormalities and by genetic linkage studies. A library highly enriched for human DNA from Xp21 was constructed using DNA isolated from a male patient who had a visible deletion and three X-linked disorders (DMD, retinitis pigmentosa and chronic granulomatous disease). Seven cloned DNA probes from this library and the probe 754 (refs 5, 8) are used in the present study to screen for deletions in the DNA isolated from 57 unrelated males with DMD. Five of these DMD males are shown to exhibit deletions for one of the cloned DNA segments and at least 38 kb of surrounding DNA. In addition, two subclones from the same region detect four restriction fragment length polymorphisms which exhibit no obligate recombination with DMD in 34 meiotic events. These new DNA segments will complement the existing Xp21 probes for use in carrier detection and prenatal diagnosis of DMD. Elucidation of the end points of the five deletions will help delineate the extent of the DMD locus and ultimately lead to an understanding of the specific sequences involved in DMD.