Blood requirements

Blood collection and shipping instructions – including cord blood


Blood is not accepted if the patient has ever received an allogeneic bone marrow/stem cell transplant. For patients who pursue genetic testing, DNA from cultured fibroblasts is the required specimen type. GeneDx can provide a punch biopsy kit and can culture fibroblasts on site, as needed.


Complimentary blood kits are available for US and Canadian clients. To order kits, please visit our request supplies page or email


One EDTA (lavender top) tube containing 2-5 mL whole sterile blood. Several tests usually can be performed on one 3 mL blood specimen. 3-5 mL is the preferred volume for adults but 1-2 mL is acceptable for infants.


Label with the patient name plus a second identifier such as date of birth, specimen ID or medical record number. If Cord Blood, state so on both the tube and the paperwork.


Can be refrigerated up to 7 days before shipping. Blood specimens older than 7 days can still be shipped; they will be tested if the yield and quality of DNA permit.


Blood specimens will be rejected if frozen, hemolyzed or clotted.


Ideal handling is to ship immediately at ambient temperature for overnight delivery with arrival Monday-Saturday. Specimens can be refrigerated for 7 days before shipping. In hot weather a cool pack can be enclosed.

Ship to
GeneDx, 207 Perry Parkway, Gaithersburg MD 20877
Phone: 1-301-519-2100