Abstract

Recent studies suggest that a non‐isotopic in situ hybridisation (NISH) approach can be successfully employed to investigate the carrier status of female relatives in families of selected patients with Duchenne muscular dystrophy (DMD) or Hunter syndrome, whose diseases are due to a specific X chromosome deletion.Whilst the majority of metaphase spreads from normal females show specific hybridisation signals on both X chromosomes when tested with either dystrophin or Hunter gene‐derived probes, only one X chromosome in each metaphase spread will show the relevant hybridisation complex in female carriers of deletions involving the dystrophin or Hunter gene.Thus, the NISH method can be a valuable diagnostic tool for the detection of the carrier status of female relatives of patients with X chromosome deletions.