title: Trisomy 18 in monozygotic twins with discordant phenotypes.
abstract: The incidence of trisomy 18 in monozygotic twins is approximately 1 per million. We report a pair of liveborn monozygotic twins with trisomy 18. Both twins had esophageal atresia with tracheoesophageal fistula (type C) and intrauterine growth retardation. Twin A had cleft lip, choanal atresia and perimembranous ventricular septal defect. Twin B had hypoplastic left heart syndrome. The twins died without aggressive intervention at the age of 2 months and 52 hours, respectively. These 2 babies had significantly discordant phenotypes, which suggests an epigenetic or environmental effect. Bioethical considerations remain important in the care of babies with multiple congenital anomalies.
authors.affiliation: Department of Pediatrics, National Taiwan University Hospital and National Taiwan University, College of Medicine, Taipei, Taiwan.
authors.forename: Jiahn-Te
authors.initials: JT
authors.lastname: Lee
authors.forename: Hung-Chieh
authors.initials: HC
authors.lastname: Chou
authors.forename: Po-Nien
authors.initials: PN
authors.lastname: Tsao
authors.forename: Wu-Shiun
authors.initials: WS
authors.lastname: Hsieh
authors.forename: Wuh-Liang
authors.initials: WL
authors.lastname: Hwu
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics; D002887:Chromosomes, Human, Pair 18; D004200:Diseases in Twins / Q000235:genetics*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D010641:Phenotype; D014314:Trisomy / Q000235:genetics*; D014430:Twins, Monozygotic