Molecular Human Reproduction, Vol. 6, No. 2, 103-106,
February 2000
© 2000 European Society of Human Reproduction and Embryology
Genetic diagnosis |
Non-invasive exclusion of fetal aneuploidy in an at-risk couple with a balanced translocation
1 Division of Genetics, New England Medical Center, Boston and 2 Department of Obstetrics and Gynecology, Boston University Medical Center, Boston, MA, USA
Abstract
A pregnant woman who was a carrier for a balanced chromosome translocation [46,XX, t(1;6) (p31;q14)] and who had had six miscarriages, declined invasive testing but agreed to non-invasive prenatal diagnosis by analysis of fetal cells in maternal blood. Monoclonal antibody (Mab) against the zeta (z) and gamma (
) chains of embryonic and fetal haemoglobin were used to identify fetal nucleated erythrocytes (FNRBC). There were no FNRBC detected at 7 weeks, one anti-z-positive FNRBC was detected at 11 weeks, and 12 anti--positive FNRBC were detected at 20 weeks. Fluorescent in-situ hybridization was performed using probes for chromosomes X, Y, 1 and 6 to identify fetal gender and the presence of an unbalanced chromosomal translocation. A tentative prenatal diagnosis was made of a female fetus disomic for chromosomes 1 and 6. A female infant with a 46,XX karyotype was born at term. This is the first attempt of exclusion of a chromosome translocation using fetal cells isolated from maternal blood. There is an advantage of using fetal cells isolated from maternal blood for non-invasive prenatal diagnosis in couples who have a history of multiple miscarriages due to a parental translocation, and who decline invasive testing in a pregnancy that continues to the second trimester.
chromosomal translocation/fetal cells in maternal blood/fetal nucleated erythrocytes/FISH/non-invasive prenatal genetic diagnosis
Notes
3 To whom correspondence should be addressed at: Division of Genetics, Department of Pediatrics, New England Medical Center, Tufts University School of Medicine, NEMC #394, 750 Washington Street, Boston, MA 02111, USA