Ordering Information

Questions about obtaining consent for genetic testing? Reference our handout or reach out to our genetic counselors.

Ordering Policies

Ordering from within Johns Hopkins? See our specific instructions for internal orders.

Sample Requirements

Labeling: Specimens require at least two (2) patient identifiers that match the specimens with the accompanying paperwork. We are not able to test samples that are not properly identified. Accepted identifiers include patient name and date of birth (preferred), or internal identifiers such as specimen ID or medical record number.

Transfusion/Transplant History: In certain situations, transfusions and transplants can impact the accuracy of genetic test results. Please review the guidelines for specimen collection from individuals who have received a transfusion or transplant. If you have any further questions, please contact the lab prior to specimen collection.

  • If your patient has received a transfusion of packed red blood cells (pRBCs) or leukocyte-reduced blood products, you can still collect/send a specimen, as this will not affect genetic testing. If your patient has had any other type of transfusion, you must wait until at least two (2) weeks after the transfusion date to collect a specimen for genetic testing.
  • If your patient has ever received an allogenic bone marrow or stem cell transplant, cultured fibroblasts are only acceptable specimen type.

Prenatal Testing: All prenatal tests will include maternal cell contamination studies and must be accompanied by a maternal blood or saliva specimen.

Shipping Instructions

Please ship samples to:

Johns Hopkins Genomics - DNA Diagnostic Lab
1812 Ashland Ave
Sample Intake; Room 245
Baltimore, MD 21205


  • The lab is not open on weekends or holidays. Check our holiday schedule to see when the lab is closed. When the lab is closed, no personnel will be present to answer phone calls or accept deliveries. Please plan your specimen shipments accordingly.
  • Specimens should be accompanied by:
    • Completed test requisition form
    • Appropriate family history and/or medical information for the test being ordered. See individual test descriptions for specific requirements.
    • Payment information. Testing will not be initiated until financial responsibility is established. See the billing page for details.
  • Shipping fees are the responsibility of the sender or patient. Johns Hopkins Genomics does not cover these fees as part of our service. Do not select "Bill Recipient" when sending a sample to the laboratory.
  • The International Air Transport Association (IATA) issues regulations for shipping dangerous goods (including infectious agents and diagnostic specimens). Specimens being sent to the JHUDDL should be shipped in packaging that complies with IATA regulations:
  1. Sealed, leak-proof primary receptacle.
  2. Leak-proof secondary packaging with absorbent material.
  3. Outer packaging of adequate strength, marked "Exempt human specimen".
  4. Please visit IATA for details or contact the lab with questions.
  • Shipment of medical diagnostic specimens is also regulated by the FAA and individual overnight courier services. Please consult your courier for their specific packaging requirements and acceptable shipping options for medical specimens.
  • General packaging guidelines include wrapping glass tubes in absorbent padding, including at least one water-tight barrier in the packaging, and always mailing specimens in a sturdy box. Your courier service may also require a special outer envelope identifying the package as a biological substance.