title: Noninvasive fetal RHD genotyping by maternal plasma with capillary electrophoresis.
abstract: BACKGROUND
  Recently, a more accurate and reliable screening test has been investigated for noninvasive prenatal fetal RHD genotyping from D- women. The objective of this study was to perform the new method of noninvasive fetal RHD genotyping with maternal plasma from D- women by use of capillary electrophoresis.
  
  
  METHODS
  Blood samples were obtained from 8 D+ and 8 D- nonpregnant donors and mixed to make test plasma samples. DNA was extracted and the appropriate conditions relating to the initial sample volume as well as polymerase chain reaction cycle numbers were analyzed to detect the RHD gene with RHD exon 10 primer. Blood samples were also obtained from 13 D- pregnant women ranging from the 12th to 39th weeks of gestation. The presence of the RHD gene and Y-chromosome-specific STR (Y-STR) derived from the fetus was analyzed. The results were compared with the D status of newborns.
  
  
  RESULTS
  In samples from 12 D- pregnant women, the RHD gene was detected. In one sample, the RHD gene was not detected but Y-STR loci were demonstrated in this sample, indicating a D- male baby. The results of fetal genotyping were all in concordance with the postpartum samples by serologic tests on D as well as with the sex of newborns.
  
  
  CONCLUSIONS
  Capillary electrophoresis can be used for the determination of fetal RHD status in D- women. This diagnostic method is useful for the noninvasive prenatal diagnosis of the fetal RHD genotyping from D- women.
authors.affiliation: Department of Obstetrics and Gynecology, Saitama Medical University, Saitama, Japan. mseyama@saitama-med.ac.jp
authors.forename: Machiko
authors.initials: M
authors.lastname: Kimura
authors.forename: Chiaki
authors.initials: C
authors.lastname: Sato
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hara
authors.forename: Osamu
authors.initials: O
authors.lastname: Ishihara
authors.forename: Kenji
authors.initials: K
authors.lastname: Ikebuchi
mesh_terms: D019075:Electrophoresis, Capillary / Q000379:methods*; D005260:Female; D005333:Fetus / Q000276:immunology / Q000378:metabolism*; D005838:Genotype; D006801:Humans; D009035:Mothers; D011247:Pregnancy; D012204:Rh-Hr Blood-Group System / Q000097:blood* / Q000235:genetics* / Q000276:immunology
chemical_list: D012204:Rh-Hr Blood-Group System