The use of maternal plasma for prenatal RhD blood group genotyping.
Alloimmunization to the blood group antibody anti-RhD (anti-D) is the most common cause of hemolytic disease of the fetus and newborn. Knowledge of fetal D type in women with anti-D makes management of the pregnancy much easier and avoids unnecessary procedures in those women with a D-negative fetus. Fetal D typing can be performed by detection of an RHD gene in cell-free DNA in the plasma of D-negative pregnant women. The technology involves real-time quantitative polymerase chain reactions targeting exons 4, 5, and 10 of RHD, with the exons 4 and 10 tests performed as a multiplex. Testing for SRY in multiplex with the RHD exon 5 test provides an internal control for the presence of fetal DNA when the fetus is male. Fetal D typing has become the standard of care in England in pregnant women with a significant level of anti-D.
International Blood Group Reference Laboratory, NHS Blood and Transplant, Bristol, UK.
Kirstin
K
Finning
Pete
P
Martin
Geoff
G
Daniels
D004247:DNA / Q000097:blood / Q000235:genetics* / Q000276:immunology; D004739:England; D004899:Erythroblastosis, Fetal / Q000097:blood / Q000175:diagnosis / Q000235:genetics; D005091:Exons / Q000235:genetics* / Q000276:immunology; D005260:Female; D006801:Humans; D007518:Isoantibodies / Q000097:blood / Q000276:immunology; D008297:Male; D010949:Plasma; D016133:Polymerase Chain Reaction / Q000379:methods*; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D012204:Rh-Hr Blood-Group System / Q000097:blood / Q000235:genetics* / Q000276:immunology; D018029:Rho(D) Immune Globulin
D007518:Isoantibodies; C061961:RHO(D) antibody; D012204:Rh-Hr Blood-Group System; D018029:Rho(D) Immune Globulin; C026410:Rho(D) antigen; D004247:DNA