AsianScientist (Mar. 11, 2014) – Two scientists from Hong Kong and the United Kingdom predict that the benefits of non-invasive prenatal testing (NIPT) will make it the main test pregnant women will go through in the future.
Fetal genetic testing has until recently needed invasive diagnostic procedures (amniocentesis or chorionic villus sampling) which carry a small but significant risk of miscarriage. However the presence of cell-free fetal DNA (cffDNA), which comes from the placenta and can be detected from the first trimester of pregnancy onwards, has changed the practice and is used for detecting certain conditions.
Obstetricians currently use cffDNA to guide women whose baby is at risk of hemolytic disease of the fetus and newborn (HDFN), a condition where antibodies develop in a pregnant woman’s blood and subsequently destroy the blood cells of the baby she is carrying. It is also used for fetal sex determination in pregnancies at a high risk of sex-linked genetic conditions.
Advantages include the possibility of detecting, without risk to the pregnancy, diseases that may have potentially serious consequences and secondly it is much more accurate than any of the previous screening tests.
However the disadvantage is that pregnant women may occasionally be informed of findings of uncertain significance, such as when there is a discrepancy between the chromosomal makeup of the cells in the placenta and the cells in the baby, known as placental mosaicism. This can result in a healthy pregnancy, however, in some pregnancies it can lead to complications.
The paper also states that due to the high degree of accuracy of NIPT, even early in the pregnancy, it will become easier to find out the sex of the fetus at an early stage. This has a number of socio-ethical implications.
Excellent communication between women and health professionals is therefore essential to understanding the implications of the test results, say the authors.
Professor Dennis Lo, FRS, Director of the Li Ka Shing Institute of Health Sciences at The Chinese University of Hong Kong, and co-author of the paper said:
“It is very encouraging to see the emerging impact of cell-free fetal DNA analysis for non-invasive prenatal testing. This is a good example of the translation of scientific discovery into clinical practice and heralds an exciting era of genomic medicine.”
The article can be found at: Soothill and Lo. (2014) Non-invasive Prenatal Testing for Chromosomal Abnormality using Maternal Plasma DNA.
———
Source: Royal College of Obstetricians and Gynaecologists; Photo: mbaylor/Flickr/CC.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.