DETROIT — Wayne State University researchers are testing a way to determine the status of fetal chromosomes that could lead to healthier outcomes for mothers and their babies.
Supported by a two-year, $418,000 grant from the Eunice Kennedy Shriver National Institute of Child Health and Human Development, part of the National Institutes of Health, the researchers will capture human fetal cells for genetic study within the first two months of pregnancy using a newly developed, safe, noninvasive retrieval technique similar to a Pap test.
D. Randall Armant and Michael P. Diamond, M.D., professors of obstetrics and gynecology in Wayne State’s School of Medicine, are the principal investigators of the study. Susan Land, associate professor of obstetrics and gynecology, is a co-investigator.
Titled “Genetic Analysis of Human First Trimester Trophoblast in Ongoing Pregnancies,” the project targets cells called trophoblasts, which surround the blastocyst, a cluster of cells that results from successful fertilization. Researchers are particularly interested in “invasive” trophoblasts, which attach the blastocyst to the uterine wall; the cells become the placenta and the membranes that nourish and protect the developing organism.
Such cells carry genetic material from the fetus. Armant’s team will gather them through transcervical sampling, a method that uses a cytobrush inserted into the cervix. Researchers believe the technique is less intrusive than previously used methods, yields intact fetal cells and can be done as early as six to 12 weeks; doctors typically must wait 10 to 14 weeks to use other methods, which can carry more risk to mothers and fetuses.
“The earlier you get the information, the more time the doctor has to manage whatever problems are coming up during or after the mother’s pregnancy,” Armant said. “It also gives the parents more time to make decisions about the pregnancy.”
Researchers will isolate trophoblasts using immunomagnetic nanotechnology, taking advantage of unique proteins on the surface of fetal cells. Highly sensitive genetic tools capable of analyzing single cells will verify the fetal origin of captured cells before their DNA is analyzed for chromosome number.
Armant said that tests based on fetal cells obtained from the cervix eventually could alert doctors to things like ectopic pregnancy, miscarriage, preterm labor, poor fetal growth, preeclampsia, fetal Rh incompatibility and chromosome number disorders, like Down syndrome. It also could help detect inherited genetic diseases, such as muscular dystrophy, sickle cell anemia and hemophilia.
The goal is to determine if placental cells obtained from the cervix accurately represent the chromosomal status of the fetus.
“Development of this diagnostic platform for the detection of chromosome number disorders could establish an innovative approach for prenatal genetic testing that would provide immense opportunities for improving the health of mothers and their babies,” Armant said.