Sample Mix Up

Short Tandem Repeat (STR) Analysis System for Sample Mix Up

NorthGene offers a short tandem repeat (STR) analysis system for sample mix up which aims to give peace of mind and clarification where sample mix up may have occurred. Such verification procedures are essential because:

  • Suspected sample mix up can have devastating consequences with regards to incorrect diagnosis
  • Sample mix up can lead to current and future research being invalid

For more information on the prevalence and impact of sample mix up please see the following; Mislabeling of cases, specimens, blocks, and slides: a college of American pathologists study of 136 institutions. Nakhleh RE, Idowu MO, Souers RJ, Meier FA, Bekeris LG,Arch Pathol Lab Med. 2011 Aug;135(8):969-74.

Authentication Process

We offer analysis of 16 polymorphic STRs which allows cross identification of cell lines of HUMAN ORIGIN with an extremely high power of discrimination. The loci which will be tested include:

Penta E, D18S51, D21S11, TH01, D3S1358, FGA, TPOX, D8S1179, vWA, Amelogenin (for gender discrimination), Penta D, CSF1PO, D16S539, D7S820, D13S317 and D5S818.
By analysing these markers each sample can be matched and verified with a high degree of precision. The allelic data from samples can be checked against each other or known reference . We can provide a statistical probability of matching identity.

Sample Requirements

Fresh or Stored Samples

We can accept fresh and fresh frozen samples of most tissue types as well as whole blood. We can also extract DNA from FFPE material either from unstained slides or tissue blocks. Additional charges apply.

Pre Prepared Genomic DNA

Supplied DNA solution must be free of any PCR inhibitors (EDTA, proteins, polysaccharides, and DMSO) to ensure high quality test results. We recommend that DNA is prepared using spin columns.

Quantity – we require a DNA at a minimum concentration of 10ng/ul in a total of 20μ. Please enquire about analysis of samples with a DNA concentration lower the 10ng/ul

Quality – Recommended parameters for assessment are:

  • ratio of optical density at 260nm to 280 nm (A260/280) between 1.8 and 1.9
  • Optical density at 260nm to 230nm (A260/230) > than 1.5.

Instructions on Sample Transportation

DNA samples should be clearly labelled and transported frozen, on either dry or wet ice using overnight courier. Please ensure they arrive in office hours and not on a weekend. Please ensure all samples are transported appropriately following the shipment of biological materials guidelines.


An allele report for your samples will be sent as a PDF or excel file. Please indicate if you would like us to crosscheck samples against each other or a given reference sample.
Turnaround Times sample repeats and sample return

The results will be issued within 4 weeks of receipt of samples. Please enquire if a faster turnaround is required. Any problems with the sample will be communicated to the sender as soon as possible to prevent delays. In a small number of instances it may not possible to complete the analysis, most often because of poor DNA quality. Unsuccessful samples are retested. Charges for all tests will still apply where it is not possible to get a result after a retest. We can return samples if requested. Shipment charges will apply.

Pricing Schedule

Prices start at £125 per sample (Ex VAT). Discounts are available on larger sample sets greater than 10. There is a charge of £40 per sample for DNA extraction. Please be clear about the origin of the tissue sample when submitting samples.