DNA testing for natural pearls

[M.STERN]

SSEF announces a DNA testing process for making various determinations about pearls. A big step towards increased transparency in the pearl world. I just wonder how expensive the process will be for SSEF and what kinds of costs their customers will have to absorb. I have attached an article about the process below.

- Monte

http://www.ibtimes.com/pearl-dna-analysis-now-possible-method-could-help-industry-id-fakes-scientists-say-1428402

 

[GemGeek]

Thanks for posting this. It doesn't appear that it will help determine if they are natural vs cultured, but it would be great to know what species they came from. SSEF is always expanding the frontiers.

 

[Lagoon Island Pearls]

Hi Monte and welcome to P-G!

It's my understanding any post-harvest treatments will skew or render DNA testing unreliable. That pretty much precludes akoyas.

 

[mausketeer]

I'm assuming they will be using it mainly to determine the species of origin for obvious or known naturals...... will that make a big difference in value? If they do use it for cultured, since the sample comes from the drill hole, how would they know they aren't sequencing the DNA of the species that was used for the bead? (not sure I'm using the correct terminology, too many science shows running through my head!)

 

[Isi]

I think it might help them to determine recent keshis from old naturals. Here there is a real difference in value.
They have trouble too with supposed naturals which are in fact cultured with an ugly natural as a bead. Here again, DNA might help, regarding the age at least.

 

[mausketeer]

Oh yes, that makes sense. I forget about the "faked naturals". Are there a lot of those out there now?

 

[Isi]

The trouble is, precisely, this is difficult to tell !
And the financial stake is huge !

 

[Lagoon Island Pearls]

I think it might help them to determine recent keshis from old naturals. Here there is a real difference in value.
They have trouble too with supposed naturals which are in fact cultured with an ugly natural as a bead. Here again, DNA might help, regarding the age at least.

DNA testing on a cultured pearl would yield dual contribution results. One result from the outer layer of the graft recipient and the other from the nucleus which is normally a different species.

I'm not 100% sure, but I'd think hybrid Chinese FWPs would yield dual results in the same test, one from each subspecies.

Yet again, we may be overthinking the process. DNA profiling should not be confused with full genome sequencing.

I'm inclined to think they are just looking at certain markers as opposed to the entire sequence.

 

[echolovesyou]

DNA testing on a cultured pearl would yield dual contribution results. One result from the outer layer of the graft recipient and the other from the nucleus which is normally a different species.

I'm not 100% sure, but I'd think hybrid Chinese FWPs would yield dual results in the same test, one from each subspecies.

Yet again, we may be overthinking the process. DNA profiling should not be confused with full genome sequencing.

I'm inclined to think they are just looking at certain markers as opposed to the entire sequence.

I tend to agree that there are still some questions on the results they get, especially the sample size isn't big anyway. Also the test is probably not very cost-effective and involves wet chemistry (running a gel).