Combining human STR and microbial population profiling: Two case reports.

In forensic case investigations involving human traces, cell type identification has become increasingly important. No longer only the donor of a trace (sub-source level), but also the actions which could have led to the deposition of the trace ('beyond-the-source'/activity level) need to be evaluated by forensic experts. For this evaluation determining the cellular source of a DNA profile can be beneficial.

Evaluation of prenatal RHD typing strategies on cell-free fetal DNA from maternal plasma.

Background: The discovery of cell-free fetal DNA in maternal plasma led to the development of assays to predict the fetal D status with RHD-specific sequences. Few assays are designed in such a way that the fetus can be typed in RHDpsi mothers and that RHDpsi fetuses are correctly typed. Owing to the limited knowledge about the mechanism responsible for the presence of fetal DNA in maternal plasma, precautions in developing prenatal genotyping strategies must be made.

RHD(T201R, F223V) cluster analysis in five different ethnic groups and serologic characterization of a new Ethiopian variant DARE, the DIII type 6, and the RHD(F223V).

Background: The RHD phylogeny in humans shows four main clusters of which three are predominantly observed in (African) black persons. Each of the African clusters is characterized by specific amino acid substitutions relative to the Eurasian RHD allele. RH phylogeny defines the framework for identification of clinically relevant aberrant alleles.

Recurrent acute hemolytic transfusion reactions by antibodies against Doa antigens, not detected by cross-matching.

An 81-year-old male patient suffered from recurrent acute hemolytic transfusion reactions after transfusion with phenotyped cross-match-negative red blood cells (RBCs). Extensive posttransfusion workup eventually revealed Dombrock (a) (Do(a)) antibodies. Because commercially available cell panels do not allow for identification of anti-Do(a) and owing to the lack of Do(a) typing serum samples, selection of matched units of RBCs is dependent on negative cross-match results.

Rapid genotyping of blood group antigens by multiplex polymerase chain reaction and DNA microarray hybridization.

Background: In the Netherlands, 500,000 blood donors are active. Blood of all donors is currently typed serologically for ABO, the Rh phenotype, and K. Only a subset of donors is typed twice for a larger set of red cell (RBC) and/or platelet (PLT) antigens.

The highly variable RH locus in nonwhite persons hampers RHD zygosity determination but yields more insight into RH-related evolutionary events.

Background: Knowledge about paternal RHD hemi- or homozygosity is of clinical interest in alloimmunized pregnant women. D negativity in white persons is usually caused by deletion of the RHD gene. Recently, the physical structure of the RH locus and the mechanism causing the deletion of the RHD gene have been explored, enabling RHD zygosity determination in white persons by specific detection of a hybrid Rhesus box characteristic for the RHD- locus.

The Rh complex exports ammonium from human red blood cells.

The Rh blood group system represents a major immunodominant protein complex on red blood cells (RBC). Recently, the Rh homologues RhAG and RhCG were shown to promote ammonium ion transport in yeast. In this study, we showed that also in RBC the human Rh complex functions as an exporter of ammonium ions.

RHC and RHc genotyping in different ethnic groups.

Background: RH genotyping assays are mainly based on research in whites. These assays may not be reliable in a multiracial society because of the genetic variation in RH among ethnic groups.

Study Design And Methods: Five groups from different ethnic backgrounds were serologically typed for C and c and were genotyped on nucleotide C48 and intron 2 for RHC and RHc on nucleotides C178 and C307.