Monozygotic twins concordant for tracheo-esophageal fistula and discordant for the VATER association.

Monozygotic female twins were concordant for tracheo-esophageal fistula (TEF); and one twin also manifested other anomalies in the VATER association, including agenesis of the female reproductive tract. Review of the literature discloses a familial tendency for recurrence of TEF and a high concordance rate in monozygotic twins, indicating a significant genetic influence for the isolated anomaly. In the case of the VATER association, the sporadic occurrence of affected individuals and discordance in twins implicates the effect of non-genetic factors.