Mosaic trisomy 9 presenting with congenital heart disease, facial dysmorphism and pigmentary skin lesions: intricate issues of genetic counseling.

Chromosomal mosaicism for full aneuploidy involving chromosome 9 is an uncommon chromosomal abnormality. Mosaic trisomy 9 clinical manifestations are highly variable and difficult to predict. The authors present a case of mosaic trisomy 9 with typical clinical manifestations(facial dysmorphism, various internal organ malformations and severe psychomotor retardation), pigmentary mosaic skin lesions along the lines of Blaschko and evidence of maternal uniparental disomy in skin.