Mosaic trisomy 15 is a rare chromosomal anomaly syndrome principally characterized by intrauterine growth restriction, congenital cardiac anomalies (incl. ventricular and atrial septal defects, patent ductus arteriosus) and craniofacial dysmorphism (incl. hypertelorism, downslanting palpebral fissures, wide nasal bridge). Patients also present brain (e.g. hypoplastic cerebellum, ventricular asymmetry), renal (e.g. small dysplastic kidneys), and/or genital (undescended testis, small penis, hypoplastic labia majora) anomalies. Digital and skin pigmentation abnormalities have also been reported. The disease is mosaic trisomy 15 (MONDO_0015727). Also known as: Mosaic trisomy chromosome 15, Mosaic trisomy type 15, trisomy 15 mosaicism.