The Australian Red Cross Lifeblood Research and Development, which is a division of the Australian Red Cross, is conducting a study that is designed to evaluate the use of a noninvasive prenatal testing (NIPT) procedure for genotyping clinically important fetal antigens.
According to findings published recently by the Australian Red Cross, the authors of the study are seeking to utilize this blood test to establish the antigen status of a fetus. The analysis aims to assess the use NIPT massively parallel sequencing (MPS) for detection of pregnancies deemed to be at risk for fetal and neonatal alloimmune thrombocytopenia (FNAIT) and/or hemolytic disease of the fetus and newborn (HDFN) in a single test.
When can NIPT be carried out and what is involved?
The utilization of NIPT enables the extraction of cell-free fetal DNA (cffDNA) from a mother’s peripheral blood without the necessity for performing amniocentesis. The blood is subsequently examined for presence of the potential fetal antigen or antibody.
Of note, NIPT can be conducted beginning as early as 12 weeks’ gestational age (GA). Use of this testing method will require obtaining three blood samples. All of the samples need to arrive at Lifeblood within 72 hours of having been collecting.
Read more about FNAIT causes and risk factors
What are the benefits of using NIPT?
Because the NIPT technique eliminates the necessity for using more invasive, riskier sampling procedures, it is associated with a decrease in the levels of stress and trauma experienced by expectant mothers. Among women with a complicated obstetric history, this will help to inform them of their possible FNAIT or HDFN risk as early as 12 weeks’ GA.
How is an NIPT MPS assay used?
NIPT, which is used for the detection of clinically significant antigens that might be related to the occurrence of FNAIT or HDFN, is described as “a molecular blood group genotyping sequencing assay under development to predict the blood group phenotype of the fetus.”
The current research study on the use of NIPT aims to develop an MPS assay that can be utilized to predict a panel of clinically significant fetal antigens associated with cell-free DNA (cfDNA) transfusion.
NIPT MPS assays have the ability to provide fetal genotyping with the use of an extended panel of clinically significant human platelet antigens or red blood cell antigens, together with the inclusion of internal fetal control markers in a single noninvasive test system.
Because utilization of this testing has not yet been accredited, at the present time, the results obtained with NIPT MPS assays are for research use only
How can an NIPT MPS assay be used for predicting FNAIT?
NIPT can be used if concern for possible FNAIT exists and fetal prediction might be helpful.
cfDNA, which is known to contain cffDNA, is extracted from the mother’s plasma. This cfDNA is analyzed “for the presence of the gene or molecular variation responsible for (or associated with) the blood or platelet group phenotype under investigation.”
The MPS assay has a positive predictive value of greater than or equal to 99.9% and a negative predictive value of greater than or equal to 97.1%. The accuracy of the MPS assay is 98.5%, which is based on the study data.
