For the sixth GCN eDNA testing season in a row, ADAS has again correctly identified 100% of blinded eDNA samples in the 2022 GCN eDNA proficiency test. Six out of seven eDNA labs taking part identified all blinded samples correctly.

Proficiency testing is carried out independently every year to provide evidence of the quality of eDNA analysis offered by the different UK eDNA testing labs.

GCN Badge

How proficiency testing is carried out

Ten different unknown samples prepared by FAPAS and were sent to each lab for analysis. eDNA testing labs provided their own eDNA testing kits so that any level of sample inhibition and degradation could also be monitored.

Lab names are anonymised so we do not know the names of other companies taking part.

ABCDEFGHIJ 
Neg, not inhibitedInhibitedNeg, not inhibitedLow positive, not inhibitedLow positive not inhibitedNegative, not inhibitedNegative, not inhibitedLow positive, not inhibitedMedium positive, not inhibitedInhibited% Correct
0/12 n0/12 i0/12 n2/12 n2/12 n0/12 n0/12 n3/12 n10/12 n0/12 i100%

n: Sample recorded as not inhibited
i: Sample recorded as inhibited

FAPAS, who oversee the proficiency testing scheme, score results as ‘satisfactory’ if both the PCR result is correct and whether inhibition or not is recorded as expected.

Translating the results

The presence/absence of an eDNA detection within pond water samples gives a reliable indication of recent GCN presence within that waterbody.

ADAS correctly identified all 10 samples that included samples containing different levels of  GCN eDNA (low medium and high), in addition to identifying samples that had been deliberately inhibited .

In addition to determining the presence of eDNA at different concentrations, it is vital that inhibited and or degraded samples are identified as these may incorrectly score a waterbody as negative for GCN even if they are actually present. Much of the success (a positive or negative result) of an eDNA test will depend on the quality of the water sample that is provided. Whilst we do our best to resolve results recorded as indeterminate (where samples are inhibited or are extensively degraded)  we won’t always be able to determine a result from a poor water sample (generally one contaminated with high amounts of organic material, sediment, etc.). It’s always important to take a good sample to achieve a conclusive result – see our sampling guidance video for more information.

ADAS – First for eDNA analysis six years running

Ben Maddison, Head of ADAS Biotechnology said

“Since the proficiency scheme started back in 2017, we’ve scored 100% in every proficiency test. Our accuracy, speed and consistency makes us the ideal partner for anyone looking to carry out reliable bulk eDNA testing this year.”

We offer super fast-track to non-priority services (2, 5 or 10 day turn around time). Results will be sent as soon as they are ready, regardless of turnaround time chosen. Visit our eDNA service page or email eDNA@adas.co.uk to learn more and to book an analysis slot. To avoid disappointment, book your analysis slot as soon as possible.

Join the Introduction to eDNA webinar

Thursday 3 March 2022

Director of ADAS Biotechnology and founder of our eDNA analysis service Dr Helen Rees will share how the use of DNA-based techniques in the surveying and monitoring of terrestrial, freshwater and marine biodiversity has the potential to reduce costs, reduce turnaround times and improve our ability to identify or detect taxa that are difficult to find or identify.

This webinar is open to all and free to join
Register to join the webinar here