Sample requirements

A fully completed molecular genetic referral card should accompany each sample. These should be legible and fully completed with all relevant information, including:

  • Patient's name (forename and surname)
  • Date of birth
  • NHS number (if available)
  • Referring consultant and referral centre clearly stated1
  • Test requested together with relevant clinical details
  • Whether diagnostic, carrier or predictive testing is required2
  • Sample type (in section labelled 'Type')
  • Date of sample collection together with the name of the person collecting the sample
  • The urgency of a sample together with reasons for that urgency

Click here for a printable referral card:  Laboratory Genetics Referral Card.pdf . If printing, please ensure both sides of the referral card are printed.

  1. Clearly stating the referring clinician and the referral centre is necessary to ensure the resulting report is sent to the correct location. Failure to provide this information may delay testing or result in the report being sent to the incorrect location. This information is also essential to ensure that referral centres are invoiced for the correct tests.
  2. Diagnostic testing is used when testing affected individuals. Carrier testing is used to identify unaffected people who have a single copy of a gene mutation in recessive disorders. Predictive, or pre-symptomatic, testing is used to test unaffected individuals who are at risk of developing late-onset genetic disorders such as Huntington disease or hereditary cancers. Carrier testing and predictive testing requests are only accepted from a Clinical Genetics Department so that appropriate genetic counselling can be offered, with the exception of haemochromatosis referrals.

Page last updated 07/11/2022. Please note that if printed, this information is only valid on the day of printing.

Sample acceptance and rejection criteria

  • Unlabelled or incompletely labelled samples will not be accepted. Samples must be labelled with the patient's name (forename and surname) and date of birth, and it is also recommended to include a unique identifier (e.g. NHS number).
  • Blood samples that are not in EDTA tubes will be rejected apart from very rare exceptional cases.
  • Blood samples that are not in the correct tube type, or affected by a delay in transit, can compromise the quality of the test result, or result in test failure

Sample requirements for molecular genetic testing

Adults and Children: 4-6 ml blood sample in EDTA. Two 4 ml blood tubes are required for predictive testing.

Neonates and Infants: A minimum of 1 ml blood sample in EDTA.

Mouthwash/Saliva and buccal scrape: Samples may be acceptable for certain sorts of tests but results may be more difficult to obtain. Please contact the laboratory for advice on collecting saliva samples using Oragene kits, available from DNA Genotek. Instructions for collection of these samples are available on the DNA Genotek website.

Fresh tissue (e.g. spleen, skin biopsy): Please contact the laboratory before sending these samples for advice. The laboratory recommend that these types of samples are transported on dry ice.

Amniotic fluid and Chorionic villus samples: Normally referred via the Cytogenetics Department. Maternal blood samples must accompany all prenatal samples unless the laboratory already has a maternal sample.

Cord blood and Fetal blood samples: Maternal blood samples must also accompany these samples.

We ask that you do not send samples from known or suspected COVID-19 patients unless they satisfy the criteria for urgent testing and it is absolutely essential that testing is undertaken. Please contact the laboratory before sending any samples as testing will be considered on a case by case basis.

Please note that the laboratory is unable to accept blood samples or saliva samples from patients who have received a heterologous bone marrow transplant (BMT), due to the presence of donor DNA. In these patients, a buccal swab sample or a skin biopsy should be referred. Please contact the laboratory for further advice on sample requirements.

Please ensure that all samples are labelled with the patient's full name, date of birth, NHS number (if available) and the date taken. They must also be accompanied by a fully completed Referral Card (see above). Samples that are unlabelled or incompletely labelled are not accepted.

We also accept genomic DNA samples for testing. These samples should be labelled with at least two patient identifiers. Please see the specific information for each disease for guidelines on the amount of DNA required for each test type.

Please note that DNA will be extracted and stored indefinitely from all samples received, unless we are specifically asked to dispose of the DNA sample following testing.

Consent

Please note that in submitting a sample, the clinician confirms that consent has been taken i) for testing and DNA storage ii) if relevant, for the use of this sample and the information generated to be shared with members of the patients family and their health professionals.

Sample storage and transport

Samples should be sent to the laboratory as soon as possible. If necessary, blood samples may be stored at 4°C but please DO NOT FREEZE. It is recommended that fresh or frozen soft tissue samples are transported on dry ice. Samples should be transported according to established protocols (see Department of Transport Guidance for Transport of infectious substances.pdf  ) and addressed to:

East Midlands Regional Molecular Genetics Service Centre for Medical Genetics
City Hospital Campus
Nottingham University Hospitals NHS Trust
Hucknall Road
Nottingham
NG5 1PB

High risk samples

If samples are associated with known or suspected risk of HIV, HepB, HepC, vCJD or other blood borne infectious diseases, please indicate clearly on the card. Samples should be stored and transported as detailed above.