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 three days of collection.
• Volume: Adults 2-5mls, Children 1-2mls, 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
• For haemoglobinopathy and rare anaemia referrals, red cell phenotypic data is required, as specified on the referral 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 Oxford before extracting DNA from the remaining blood

Blood spot

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: 5-10ml
• Further information: samples need to be received in the lab by 12.00 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 24hrs of sampling
• Transport at room temperature (or refrigerated) to arrive within one day of collection (send by courier if necessary; delay will lead to loss of RNA within cells)
• Volume: 2ml-10ml
• Further information: samples must be received in the lab on Monday - Wednesday only

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 three days of collection
• Volume: 1cm 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 two days of sending
• Volume: ideally >50mg tissue; if quantity is limited 5-10mg 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
• Further information: February 2022: laboratories are not currently routinely accepting saliva samples due to COVID-19: please contact us for further details. Any referral must be discussed and agreed prior to sending

Urine samples (for mitochondrial genetic analysis)

• Suitable sterile container, such as 20ml Universal
• Transport at room temperature (or refrigerated) to arrive within one day of collection (send by courier if necessary)
• Volume: 20ml 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 referral forms

Fixed tissues and tissue slides (FFPE)

• Slides need to be in a slide box and packaged with sufficient padding
• Transport at room temperature (or refrigerated)

Whole Genome Sequencing (WGS)

Referral forms and 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.