Resorbed co-twin as an explanation for discrepant chorionic villus results: Non-mosaic 47,XX, +16 in villi (direct and culture) with normal (46,XX) amniotic fluid and neonatal blood |
| |
Authors: | Dr. Avirachan T. Tharapel Sherman Elias Lee P. Shulman Linda Seely Donald S. Emerson Joe Leigh Simpson |
| |
Affiliation: | 1. Division of Reproductive Genetics, Department of Obstetrics and Gynaecology, Memphis, TN 38163, U.S.A.;2. Department of Radiology, University of Tennessee, Memphis, Memphis, TN 38163, U.S.A.;3. Division of Genetics, Department of Pediatrics, Memphis, TN 38163, U.S.A. |
| |
Abstract: | Non-mosaic trisomy 16 was observed in chorionic villus cytotrophoblasts (direct) as well as cultured mesenchymal core cells derived from the pregnancy of a 38-year-old woman. Chromosome preparations from amniotic fluid and neonatal cultures (cord blood) were 46,XX. Normal fetal growth as determined by serial ultrasound examinations occurred throughout the pregnancy, which resulted in a healthy 2724 g female. Multiple biopsies taken from the umbilical cord, placental cotyledons, and fetal membranes were 46,XX. However, a placental nodule and three of six cultures initiated from membranes (amnion and chorion) showed 46,XX/47,XX, + 16 mosaicism. We propose that the trisomy 16 cells arose from residual villi derived from a trisomic cotwin that never developed. This case further demonstrates that normal fetal growth may presage normal outcome irrespective of cytogenetic findings in cytotrophoblasts (direct) and cultured mesenchymal core cells. |
| |
Keywords: | Chorionic villus sampling Trisomy 16 Prenatal diagnosis |
|
|