Galea and colleagues have used silver in-situ hybridisation (SISH) for the determination of ploidy in suspected molar pregnancy and others have adapted HER2 CISH assays to determine DNA ploidy.11, 13 The HER2 dual-colour dual-hapten in-situ hybridisation (D-DISH) assay is readily available in many pathology laboratories for determining HER2 gene amplification status in women with breast cancer. The gene discussed is ERBB2; the disease is breast carcinoma.