Background:  Rhesus factor D (RhD) or RhD antigen is the most common of the five main Rhesus antigens (C, c, D, E and e) out of 54 antigens on the surface of red blood cells. The dominant RHD gene determines whether a person is RhD-positive or -negative. Approximately 85 % of the European population is RhD-positive, around 95 % in sub-Saharan Africa and greater than 99.5 % in eastern Asia. The majority of RhD-negative Caucasians have a complete deletion of the RHD gene. In other populations such as Asians, Japanese and black Africans, the negative phenotype can also be associated with smaller genetic variations (e.g. point mutations, insertions, gene-rearrangements) resulting in non-functional RHD genes. The prediction of the fetal RHD status is significant for the prevention of fetal hemolytic disease, where a RhD-negative mother becomes sensitized to an RHD-positive fetus causing a maternal immune response to produce IgG anti-D antibodies.

Description:  FetoGnost® Kit RHD is a non-automatic in vitro diagnostic real-time PCR test for the qualitative detection of fetal RHD DNA from maternal plasma of non-immunized RhD negative women (non-invasive prenatal determination of fetal RHD status, NIPT-RHD). This test is suitable for women of all ages with gestation age ≥11+0 with singleton or multiple pregnancies. The test can be used both in a first pregnancy and in subsequent pregnancies. It allows targeted anti-D prophylaxis in RhD-negative pregnant women without anti-D alloimmunization. Contraindications:

  • Pregnant women with anti-D alloimmunization. The immunization status of the pregnant woman should be known before starting the test.
  • The test is not suitable for samples taken before gestation age 11+0. The limited performance of the test prior to gestation age ≥11+0 must be indicated on the report.
  • The test is not intended for Rhesus D determination of transfusion recipients and blood donors.
FetoGnost® Kit RHD allows a rapid, sensitive and non-invasive detection of the fetal rhesusfactor D (RHD) gene in samples purified from maternal plasma of RhD-negative pregnant women. The test is based on real-time PCR technology. Probe-specific amplification-curves in VIC, FAM and NED channels indicate the amplification of exons 5, 7 and 10 of the RHD gene of RHD positive fetuses, respectively. In addition, an internal positive control (IPC) with detection in Cy5 channel monitors the integrity of kit reagents, serves as a control for DNA extraction and excludes false-negative interpretation of results due to inhibition of real-time PCR. The target for the IPC is added during DNA extraction of maternal plasma samples. Using a 96-well reaction plate, the DNA of 30 plasma samples including controls can be analysed in triplicates (order no. HUFG100(. The sensitive and robust multiplex test format of FetoGnost® Kit RHD for the detection of three exons of the RHD gene in triplicates minimizes false-negative results.

FetoGnost® Kit RHD (IVD)
Order Number Reactions Channel Pathogen Channel IPC Target
HUFG100 100 FAM, VIC, NED Cy5 RHD Exon 5, 7, 10
HUFG500 500 FAM, VIC, NED Cy5 RHD Exon 5, 7, 10
Shipping Temperature: -20 °C to +4 °C
Product Features:
  • Amplification and detection: human RHD gen Exon 5, 7, 10
  • CE-IVD Real-time PCR with rapid hot-start Taq DNA polymerase
  • ROX™ dye as passive reference
  • Internal Positive Control System to exclude false-negative results
  • Optimized to handle PCR inhibitors
  • PCR- platforms: runs on all established standard real-time PCR- platforms
  • Harmonized thermal profiles to run RNA and DNA samples simultaneously

PCR platforms: FetoGnost® Kit RHD has been validated with the Applied Biosystems® 7500 instrument and QuantStudioTM 7 Pro (Thermo Fisher Scientific) (fast cycle parameters are not supported), but is also compatible with other real-time PCR instruments which detect and differentiate fluorescence in FAM, VIC, NED and Cy5 channels. When using PCR-platforms not tested by ingenetix, an evaluation of the multiplex-PCR is recommended.

BactoReal® , MycoReal® , ParoReal ® and ViroReal® Kits run with the same thermal cycling conditions.