National Molecular Laboratory
National Molecular Laboratory
The American Red Cross AABB-accredited CLIA licensed National Molecular Laboratory offers state-of-the-art testing services and expertise to help you care for patients in challenging situations. We support complex antibody identifications, help guide selection of compatible donors, and determine risk of alloimmunization to blood group and platelet antigens.
The laboratory also screens whole blood and platelet donors to identify donors of antigen negative blood products. The laboratory has been using red blood cell genotyping of donors since 2008 and, to date, has screened more than 300,000 blood donors.
For patients, molecular testing is a useful adjunct to complex serologic cases. It can resolve typing discrepancies, determine an extended red cell phenotype in patients wtih hemoglobinopathies, warm autoantibodies or on immunotherapies such as anti-CD38 and -CD47, and predict a red cell phenotype when serologic typing is unreliable [see Human Erythrocyte Antigen (HEA) Genotyping Panel]. It is useful to determine candidacy for Rh immune globulin in women with a serologic weak D phenotype of discordant RhD types (see RHD Genotyping for D Variants).
National Molecular Laboratory
700 Spring Garden Street
Philadelphia, PA 19123
Email: nationalmolecular@redcross.org
Phone: (215) 451-4917
Fax: (215) 451-2506
M-F 7am - 7pm EST
Director: Dr Martin CH Chou, PhD
CLIA Director: Shraddha Patel Babariya, MD
CLIA License: 39D0194473
Available Molecular Testing
Molecular genotyping is useful to predict the presence of red cell and platelet antigens. HEA (human erythrocyte antigen) and HPA (human platelet antigen) testing allows simultaneous testing for multiple antigens in one assay. Higher resolution testing, including genomic and cDNA sequence analysis is used to characterize variant antigens and resolve typing discrepancies. This testing can identify novel variants in many blood group and platelet antigen systems.
Indications for Patient Care
- Determining extended red cell phenotype in a patient who
- Was recently transfused
- Has a positive direct antiglobulin test
- Has autoimmune hemolytic anemia
- Is taking (or is going to begin taking) anti-CD38 (daratumamab) or anti-CD47 therapeutic agent
- has sickle cell disease or thalassemia
- needs long-term transfusion support
- has had a bone marrow transplant and for whom engraftment is not complete and/or has produced a red cell alloantibody
- Investigation of antigen typing discrepancy
- Resolution of weak D typing to determine risk of alloimmunization
- Rule in/out weak D types 1, 2, and 3
- Identify partial D status
- Determine candidacy for Rh immunoprophylaxis
- Determination of paternal RHD gene zygosity
- Identification of Rh variants (C, c, E, e, hrB, hrS)
- RHCE variant allele assignments for purposes of Rh genotype matching
- Evaluation of risk of hemolytic disease of the fetus or newborn (HDFN)
- Evaluation of risk of neonatal alloimmune thrombocytopenia (NAIT)
- Human Platelet Antigen (HPA) prediction for platelet refractoriness and post-transfusion purpura (PTP)
Test Methods
- Sequence-specific primer (SSP)-Polymerase chain reaction (PCR)
- PCR-restriction fragment length polymorphism (RFLP)
- Array-based genotyping for red cell and platelet antigens
- Sequence-based testing (SBT) using genomic DNA and cDNA
- Plasmid cloning of PCR products followed by Sanger Sequencing
How to Order Testing
Order Form
- For customers using Connect, please select Molecular Testing and complete the electronic form. Print a copy of the form and include with the sample.
- To submit a sample using a paper request, please complete the Molecular Testing Request Form.
- Orders placed without an ordering physician or test type selected will not be accepted.
Sample Requirements
- All samples and the Request for Molecular Testing form must be clearly labeled with the full name of the individual and a unique identification number. The information on the tube must match the information on the request form. Sample labels should also include date and time of collection.
- Samples without sufficient information for unique identification will be rejected.
- Samples less than 10 days old are preferred. DNA yield of older specimens may be low or QNS.
Sample Types
- Whole Blood: 5-10 ml EDTA (lavender top) or ACD type A (yellow top) whole blood tube. If submitting pre- and post-transplant samples, clearly label them as such and submit separate request forms. Lithium heparin sample tubes are NOT acceptable for testing
- Amniocytes: 1-5 ml amniotic fluid or 1-5x106 cultured amniocytes. A maternal blood sample is required when submitting fetal sample. Submit amniocytes and maternal samples with separate request forms
- Buccal swabs may be acceptable depending on the testing requested; contact the laboratory for more information. Buccal swabs should be air dried completely before putting in bag or envelope.
Shipping Requirements
- Ship according to Department of Transportation regulations for biological specimens.
- Whole blood sample can be shipped at room temperature or refrigerated using ice packs or wet ice sealed in plastic bags
- Amniocytes must be shipped refrigerated using ice packs or wet ice sealed in plastic bags, according to DOT regulations for biological specimens.
- Air-dried buccal swabs can be shipped at room temperature
- Wrap all samples in absorbent materials to safeguard from freezing or breakage.
- Ship all samples “Next Day” delivery or via American Red Cross courier, if applicable.