Specimen Collection

4 mL Adult EDTA Blood

0.5 mL Paediatric EDTA Blood

- EDTA Blood. Adults 4ml, Paediatric samples minimum 0.5ml.
- For neonatal unit babies, 6 punched-out circles from a dried blood spot
- For other samples, please contact the laboratory

Turnaround Time: 6 weeks

Urgent metabolic testing TAT: 72 hours

Assay Method

TEST METHOD: Sanger sequencing is performed for the targeted sequence variants and analysed using Variant Reporter Software v3. Minimum sequence trace Phred score is 35, corresponding to an average false base call frequency of 0.031%. The limit of detection (LoD) of Sanger sequencing is 15-20%. It will not detect low level mosaicism below the LoD or mosaic variants in tissues other than that submitted for testing.

Diagnostic Use and Interpretation

Clinically relevant genes associated with an inherited metabolic disorder are analysed.

IMPORTANT NOTE:
Referrals can only come from Genetic Health Service NZ (GHSNZ) or medical specialists group listed in the table below:

Disorder	Gene Name	Variant(s) Tested	Referral requirements
Very Long-Chain Acyl-CoA Dehydrogenase Deficiency (VLCAD)	ACADVL	c.1226C>T p.(Thr409Met) in exon 12	Metabolic or Genetic Services only.
Type I Citrullinemia	ASS1	c.787G>A (p.Val263Met) in exon 12	Biochemical Genetics or Metabolic Genetic Services only
Carnitine palmitoyltransferase 1A (liver)	CPT1a	Kiribase*: c.100T>C (p.Ser34Pro) in exon 2 and/or Niuaean: c.2122A>C (p.Ser708Arg) in exon 17 *This variant is believed to be sub-clinical. Testing is to confirm source of aberrant enzyme results.	Metabolic or Genetic Services only. All requests to be referred to Dr Callum Wilson for review.
Galactosaemia (classic and Duarte variant only)	GALT	Classic: p.Ser135Leu (exon 5), p.Gln188Arg (exon 6), p.Leu195Pro (exon 7), p.Tyr209Cys (exon 7), p.Lys285Asn (exon 9) Duarte: (D2) p.Asn314Asp (exon 10), 119_116delGTCA (5'UTR). (D1): p.Leu218Leu (exon 7), p.Asn314Asp (exon 10)	Metabolic or Genetic Services only.
Batten's disease, MFSD8-Related Neuronal Ceroid-Lipofuscinosis	MFSD8	c.103C>T (p.Arg35X) in exon 3 and/or c.479C>T (p.Thr160Ile) in exon 6	Metabolic or Genetic Services only. All requests to be referred to Dr Callum Wilson for review.
Thiopurine methyltransferase - pharmacogenetic testing	TPMT	Exons 4, 8 and 9	Specialist Chemical Pathology

Contact Information

To contact the Molecular Genetics team:

Auckland City Hospital	(09) 307 4949
Lablink	ext 22000
Molecular Genetics Office	ext 22014

Specimen Transport Instructions for Referring Laboratories

Transport all bloods between >8 degrees C to <24 degrees C within 24-48 hours. If necessary specimens can be refrigerated overnight for transport at the temperatures stated above the following day.

For testing of other sample types please contact the laboratory prior to sending.

Last updated at 15:18:53 09/09/2024