Non-invasive prenatal genetic test is accurate five weeks into pregnancy
The latest developments in prenatal technology conceived by scientists at the Wayne State University School of Medicine that make it possible to test for genetic disorders a little more than one month into pregnancy were revealed.
In the article, the WSU researchers wrote that their non-invasive testing method – Trophoblast Retrieval and Isolation from the Cervix (TRIC) – offers the accuracy of more invasive tests, such as the needle-directed amniocentesis, and can also be utilized five to 10 weeks earlier than current testing modalities.
TRIC was first publicized in 2014 in studies led by principal investigator and Professor of Obstetrics and Gynecology D. Randall Armant, Ph.D. The method isolates several hundred foetal cells that migrate from the placenta into the uterus using a retrieval technique akin to the common Pap smear, and can be done as early as five weeks into pregnancy.
Armant’s co-principal investigator in the latest research is Associate Professor of Obstetrics and Gynecology Sascha Drewlo, Ph.D., who joined the team in 2014 to provide expertise in molecular biology and perinatal medicine.
A related paper published by the two “Altered Biomarkers in Trophoblast Cells Obtained Noninvasively Prior to Clinical Manifestation of Perinatal Disease,” describes the correlation between the levels of certain proteins in the foetal cells isolated by TRIC during the first trimester and the development of intrauterine growth restriction, which results in a small, undernourished foetus in the womb, or preeclampsia – hypertension and kidney disorder of the mother – in the last trimester.
“This finding suggests that it might one day be possible to test these protein levels to identify pregnancies at risk for complications. Such a test could help physicians to better manage the health of mother and baby, and would streamline research on new interventions to prevent or limit the effects of disease,” Armant said.
The paper demonstrates the researchers’ ability to isolate foetal DNA from the cells obtained by TRIC. Since the placenta is derived from the embryo and its DNA is the same as that of the foetus, the researchers can use cells obtained by TRIC for prenatal genetic testing. The paper was co-first authored by Chandni Jain, Ph.D., and Leena Kadam, working in the laboratories of Armant and Drewlo.
“We sequenced the foetal DNA and compared it to that of the mothers, proving that they were different, but the foetal DNA always contained one copy of the mother’s DNA genes. We also had some DNA from the placenta and found that it was identical to the foetal DNA,” Armant said.
The sequencing was completed in 20 consecutive pregnancies collected at five to 19 weeks, with minimal maternal DNA contamination.
Wayne State Universityresearch.wayne.edu/news/studies-reveal-wsu-conceived-non-invasive-prenatal-genetic-test-is-accurate-five-weeks-into-pregnancy-21140
