For a long time, it was thought impossible to isolate a pearl's genetic material. Now, a Swiss research team has achieved this elusive goal. Scientists Joana Meyer, from the ETH Institute of Integrative Biology group headed by Prof. Bruce McDonald, and Laurent Cartier of the Swiss Gemmological Institute (SSEF), under the direction of Michael Krzemnicki, succeeded for the first time in extracting trace amounts of DNA from a variety of cultured pearls in an almost non-destructive way. Using the genetic code, they were able to differentiate pearls from three different species of oysters vital to the jewellery trade. Their results were recently published in the scientific journal PLoS ONE.
The genetic material is likely embedded in organic matter found in the calcium carbonate matrix of the pearl, as well as in random pockets of organic matter enclosed in the pearl. The tiny amount of DNA recovered was sufficient to determine the species of pearl oyster that produced the jewel in question. The examined pearls were South Sea pearls originating from the species Pinctada maxima, Tahitian pearls from Pinctada margaritifera and pearls from Akoya oysters. This last group is one of the most important producers of both cultured and natural pearls (Pinctada radiata). These naturally formed gems can be very valuable and often come from the Arabian Gulf.
An important part of the project was to develop a technique for isolating pearl DNA without destroying the commercial value of the jewels. The researchers used a fine drill to expand existing holes in a barely visible way. The resulting 10 milligrams of drilled-out material was sufficient to isolate enough DNA for the purpose of species identification.
A patent application has already been filed for the method developed by the research team. In the future, it will be possible to use it to differentiate between various kinds of pe
|Contact: Bruce McDonald|