SWGLH Requesting a genomic test for Rare Disease

Eligibility criteria for the rare diseases can be found in the National Genomic Test Directory (NGTD)

• The Rare Disease tests are performed at both Bristol and Exeter laboratories dependent on the type of test request, as defined in this document:

• Most genomic tests can be performed on peripheral blood samples collected into EDTA tubes.
  • Please send at least 1ml for neonates, 2-5ml for adults/children. 
  • For cytogenetic analysis, for example karyotyping of Fluorescent in situ hybridisation, a blood sample in Lithium Heparin (2-5ml for adults/children and 1-2ml for neonates) is required.
  • Blood samples should be kept at room temperature or at 4oC and not be frozen before dispatch.
  • They should be sent to the SWGLH to arrive within 1-3 days of sample collection.
  • Chorionic villus samples or products of conception should be sent in transport media, if you require this please contact the laboratory.
  • Testing for facioscapulohumeral muscular dystrophy (FSHD) requires a larger volume of blood - minimum of 8ml in an EDTA tube is requested.
• In special circumstances, a saliva sample is acceptable. Please contact the SWGLH for saliva sample collection kit. For other diagnostic material, including extracted DNA (5µg minimum) or paraffin embedded blocks, please contact the SWGLH, details below
• We recommend that clinicians follow local Trust policy regarding consent for rare disease diagnostic testing.

•  All samples for rare disease genomic testing should be accompanied by a fully completed request form
• The request form should include as much clinical information about the patient or family member, family relationships and the requested test code (R number).
• The Electronic request form is for use for the majority of Rare Disease clinical indications. It may also be used for phlebotomy and requests for DPYD.

•  In most cases, samples and request forms will be sent by clinicians to their local Pathology reception before dispatch to one of the SWGLH using the using Pathology intersite transport services ​

• Samples may also be posted by Clinical teams or by local Pathology services by first class or courier

• Packaging should comply with UN3373 regulations for packaging and transportation of samples:

  • The sample should be wrapped in enough tissue to absorb the entire contents of the tube in the event of a breakage.
  • Seal the tissue with tape and place it into a specimen bag and seal.
  • Samples should then be placed in a sample box or padded envelope with the request form and the package marked ‘Pathological Specimen – Fragile With Care’

• See the sample requirement and transport pages for further details

• The GLH network aims to report rare disease genomic test results according to national guidelines:
  • Standard single gene and small gene panel (<10 gene) sequencing - 42 days (6 weeks)
• Clinically urgent tests will be prioritised. Please note the reason for urgent testing on the request form and contact the laboratory by e-mail to notify requests in advance for prenatal diagnosis.