Specimen requirements - molecular genetics - constitutional analysis

Details of specific sample requirements for molecular genetic tests are provided below.

Blood samples - DNA extraction and molecular testing

• EDTA tubes only*
• Transport at room temperature (or refrigerated) to arrive within 3 days of collection
• Volume: Adults 2 - 5 mls, Children 1 - 2 mls, Fetal / Neonates 1ml
• *Further information: Lithium heparin (LiHep) and Sodium Citrate (NaCitrate) samples are accepted for Factor V Leiden / common Prothrombin and HFE genotyping tests

Blood spots

Transport at room temperature (or refrigerated).

Blood samples - NIPD samples

• Streck tubes (EDTA can be used if Streck tubes unavailable but requirement to arrive within 24 hours is then critical)
  
• Transport at room temperature to arrive within one day of collection (send by courier if necessary)
• Volume: 5 - 10 ml
• Further information: samples need to be received in the lab by 12 noon on a Thursday and not on a Friday; do not refrigerate or freeze samples

Blood samples - for RNA extraction

• PaxGene tube: EDTA can be sent, but needs to be received within 24 hrs of sampling
• Transport at room temperature (or refrigerated) to arrive within 1 day of collection (send by courier if necessary; delay will lead to loss of RNA within cells)
• Volume: 2 ml - 10 ml
• Further information: samples must be received in the lab on Monday to Wednesday only

Blood samples - haematology phenotyping

For haemoglobinopathy and rare anaemia referrals, red cell phenotypic data is required, as specified on the request forms.

If the referrer is unable to provide full blood count results or HPLC (or equivalent) results, then we may be able to undertake them in the Oxford Haematology Laboratory before extracting DNA from the remaining blood.

EDTA tubes only

Transport at room temperature (or refrigerated) to arrive within 3 days of collection

Volume: Adults 2 - 5 mls; Children 1 - 2 mls; Fetal / Neonates 1 ml (only a few microlitres are used for the haematology tests but the remainder is required for DNA extraction)

Bone marrow aspirate samples DNA extraction and molecular testing

• EDTA tubes only
• Transport at room temperature (or refrigerated) to arrive within 3 days of collection.
• Volume: Adults 2 - 5 mls; Children 1 - 2 mls; Fetal / Neonates 1 ml
• Typically only used for non-malignant haematology genetics

Tissue samples

• Muscle / liver biopsies for mitochondrial analysis are listed separately
  
• Samples should be sent dry in a plastic sterile container
  
• Transport at room temperature (or refrigerated) to arrive within 3 days of collection
  
• Volume: 1 cm square of the tissue is sufficient for the extraction of DNA
• Further information: do not fix these tissues (e.g. avoid use of formalin)

Muscle / liver biopsies (for mitochondrial genetic analysis)

• Samples should be snap frozen immediately in liquid nitrogen
• Can be stored at -80°C prior to sending
• Transport by courier on dry ice to arrive within 2 days of sending
• Volume: ideally > 50 mg tissue; if quantity is limited 5 - 10 mg may be sufficient
• Further information: notify lab to expect receipt

Saliva samples

• Oragene DNA collection vials (supplied on request by the lab)
• Once the saliva sample has been mixed with the Oragene DNA solution it is stable at room temperature for a few years (refer to the manufacturer's collection protocol supplied with each kit)
• Transport at room temperature (or refrigerated)
• Volume: as per manufacturers collection protocol supplied with each kit

Buccal samples

• Tissue Transport Medium and buccal brush (supplied by the lab)
• Transport at room temperature (or refrigerated) to arrive within 1 day of collection (sample should be sent without delay as any delay may impact test performance)
• The clinician must confirm that the patient was not known or suspected to have COVID-19 infection at the time of sampling: a COVID exemption form should be sent with the sample

Urine samples (for mitochondrial genetic analysis)

• Suitable sterile container, such as 20 ml Universal
• Transport at room temperature (or refrigerated) to arrive within 1 day of collection (send by courier if necessary)
• Volume: 20 ml of an early morning sample
• Further information: please contact us if further advice is required

DNA samples

• Transport at room temperature (or refrigerated)
  
• Volume: required amounts are dependent on the tests requested - as a guide exome analysis needs 3ug at a concentration no less than 30ng/ul but less DNA is required for other tests: contact us for more information
• Further information: overnight courier transport is preferable for urgent samples, e.g. for prenatal analysis
  
• If sending DNA samples for non-malignant haematology tests, please first ensure that you have all the required blood results for the request forms

Postmortem fixed tissues for extraction

• Paraffin embedded tissue - 10 x 10 µm rolled sections in two sterile microtubes (5 sections in each)
• Material can be sent at room temperature

Whole Genome Sequencing (WGS)

Sample requirements for whole genome sequencing are available on the website: West Midlands Regional Genetics Laboratory

For specific queries about WGS email: bwc.centralsouthglh@nhs.net

Notes

Additional sample types may be accepted for analysis.

For additional sample types please contact us to discuss specific specimen requirements prior to arranging specimen collection.