Mosaic trisomy 12 diagnosed in a female patient: clinical features, genetic analysis, and review of the literature

Mosaic trisomy 12 is a rare genetic condition with a highly variable phenotype.Clinical features associated with this condition include developmental delay,intellectual disability,dysmorphic facial features,short stature,pigmentary dysplasia,complex congenital heart defects and hypotonia(Table 1).To date,20 patients have been described in which mosaic trisomy 12 was observed in both extraembryonic and neonatal/infant tissues.