A Rare Cohort of Two Rhnull Individuals
Richard R Gammon1, Alexander Delk2, Patricia Houtz3
1Immunohematology Reference Laboratory-Cypress Creek, OneBlood, Inc., Ft. Lauderdale, Florida.
Laboratory Medicine
|June 14, 2020
Summary
Rhnull blood type identification requires both serological and molecular testing. Historical molecular testing missed a rare Rhnull donor, highlighting the need for comprehensive evaluation.
Area of Science:
- Hematology
- Genetics
- Immunohematology
Background:
- The Rhnull blood group phenotype is extremely rare, characterized by the absence of all Rh antigens.
- Individuals with Rhnull blood require specific transfusion support due to the risk of alloimmunization.
Observation:
- A patient with a history of Rhnull status required platelet transfusion.
- A directed donor, previously identified as Rhnull, was re-evaluated.
- Initial molecular testing of the donor showed an r'r' phenotype, conflicting with historical data.
Findings:
- Serologic testing confirmed the patient's Rhnull status and presence of anti-Rh29 antibodies.
- Re-testing of the donor's historical sample using tube testing confirmed Rhnull phenotype.
- Human erythrocyte antigen BeadChip (HBC) molecular testing limitations were identified, as it can miss certain null phenotypes.
Implications:
- This case underscores the critical need for combined serological and molecular methods in Rhnull blood typing.
- Accurate identification of rare blood types is crucial for transfusion safety and donor selection.
- Limitations of molecular genotyping techniques for detecting all null phenotypes must be recognized.
Keywords:
RHAGRh blood group systemantibodies to high prevalence antigensantigen testingantigen testing by DNAcomplex antibody identificationhigh prevalencenull typesplatelet transfusionMore Related Videos
10:53Isolation of Cognate RNA-protein Complexes from Cells Using Oligonucleotide-directed Elution
Published on: January 16, 2017
9.4K
10:08Genetic Mapping of Thermotolerance Differences Between Species of Saccharomyces Yeast via Genome-Wide Reciprocal Hemizygosity Analysis
Published on: August 12, 2019
17.5K
Related Concept Videos
01:19Rh Blood Group
2.5K
The Rhesus (Rh) antigen is crucial in determining blood groups and ensuring compatibility during blood transfusions.
2.5K
02:20Blood Types
22.0K
Human blood is classified into different types based on the presence of antigens on the red blood cell's surface and antibodies in the plasma. Proper identification of blood type is essential for successful blood transfusion. The International Society of Blood Transfusion has identified 38 human blood types based on the surface antigens on the red blood cells. The most common types are ABO, Rh, and MNS blood types.
ABO blood group
ABO antigens are glycoproteins encoded by genes present on...
ABO blood group
ABO antigens are glycoproteins encoded by genes present on...
22.0K
02:41Lethal Alleles
17.5K
Agouti: A Lethal Allele
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
17.5K
01:49Hardy-Weinberg Principle
75.7K
Diploid organisms have two alleles of each gene, one from each parent, in their somatic cells. Therefore, each individual contributes two alleles to the gene pool of the population. The gene pool of a population is the sum of every allele of all genes within that population and has some degree of variation. Genetic variation is typically expressed as a relative frequency, which is the percentage of the total population that has a given allele, genotype or phenotype.
75.7K
01:29Nondisjunction
81.5K
During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.
81.5K
01:21Nondisjunction
4.6K
Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate correctly and move to the opposite poles of the cells. This produces daughter cells with abnormal chromosome numbers. Nondisjunction is common during anaphase I or anaphase II of meiosis. Mutations in synaptonemal complex proteins that attach homologous chromosomes increase the chances of nondisjunction in anaphase I of meiosis I. In contrast, mutations in topoisomerases and condensins that hold...
4.6K