SINGLE-CELL ANALYSIS OF THE RHD BLOOD-TYPE FOR USE IN PREIMPLANTATIONDIAGNOSIS IN THE PREVENTION OF SEVERE HEMOLYTIC-DISEASE OF THE NEWBORN

OBJECTIVE: Our purpose was to develop a molecular assay to determine t he fetal RhD blood type on single diploid cells, including blastomeres . STUDY DESIGN: Polymerase chain reaction amplification of a 99 bp deo xyribonucleic acid fragment of the RhD gene or a 113 bp fragment from the RhCE gene was performed from 20 venous blood samples and 20 amniot ic fluid samples and from 60 single-cultured lymphoblasts and 12 media blanks mixed in a blinded fashion. This reaction was similarly tested after whole-genome amplification on 10 lymphoblasts and seven human b lastomeres. RESULTS: Deoxyribonucleic acid amplification was successfu l and correct from all genomic deoxyribonucleic acid samples. Ninety-s even percent of single cells amplified; correct diagnosis was made in 96%. Five blastomeres successfully amplified. No media blanks produced amplified, contaminating deoxyribonucleic acid. CONCLUSIONS: The RhD blood type can be determined reliably from single cells and can be use d for preimplantation genetic diagnosis for the prevention of rhesus h emolytic disease.