StarryPearl's thread

[StarryPearl]

Earlier this week, I received a set of beautiful T pearls that I found to match the peacock T pair I shared. They are not drilled yet. One or two of them if looked at closely are high button pearls. I am a bit hesitant whether I would like to drill them the conventional way, or from side to side.


Before sharing the pictures, I'd like to finally revisit the DNA fingerprinting paper. Honestly, I didn't understand the paper 100%, and my head is filled with tons of big and small question marks. I probably missed important information, too. Nonetheless, I'll ask a few here. Would appreciate if anyone bothers to answer, and all discussion is welcome.

1. I learned PCR-RFLP and understand how complicated it is. While I was reading the paper, I was wondering why they didn't directly do the sequencing of relevent genes (the "four target loci") on the PCR amplified adductor muscle specimens' DNAs and the pearl specimens' DNAs and just run a comparision of the sequences? Intuitively, same species' muscle DNA and pearl DNA would match, right? Why did they have to go through the whole complicated process of RFLP? Even 11 years ago, sequencing was not very expensive. I found online that in 2014, the cost of a human genome sequence dropped to $1,000. And that's a whole human genome's price we're talking about. A few specific oyster genes should be so much cheaper. Wikipedia also says "RFLP analysis is now largely obsolete due to the emergence of inexpensive DNA sequencing technologies". So, why did this group of researchers choose to use the complicated RFLP instead?

2. The method and logic in the paper seems to be based on the assumption that the DNA obtained from the pearl is the DNA of the oyster that carried the pearl, or at least the same species with that oyster. So I am curious, what is those organic matter between the bead and the nacre? I suspect that's the debris of the donor mantle tissue, is that correct? The epithelial cells in the donor tissue reproduce and develope into the pearl sac, but the tissue itself cannot 100% turn into the sac, and therefore some debris was trapped inside, am I understanding correctly?

3. To continue Question 2, I'm also curious: do ALL oysters EXCLUSIVELY use donor tissue from the same species for pearl production? I know that's what farmers do all the time, but is it a guarantee, like a 100% thing? Has anyone ever tried to put SoC pearl's tissue in Tahitian's shell, hoping to make large quantity SoC pearls? (Well, might need a new name if succeeded, LOL!) If that's too difficult because they are from different genera, how about P. Penguin's tissue into P. Sterna's oyster? Although SoC shell is smaller, it seems to produces decent size pearls more easily than Mabe Gai does. Did anyone ever try? If not, will it be possible? I understand even same species grafting already has a high death rate, and it would be intuitive to think cross-species and cross-genus will lead to even worse rate. But, if SoC could become more abundant and affordable, if Mabe Gai full pearls were more often seen on the market (instead of in a myth), how wonderful would that be...


Apologies for my crazy questions. According to a UK study, a lack of sleep lead to a lack of self-control. I was only able to sleep <4 hours last night and I feel like I'm sleepwalking all day today. So I forgive myself.

All in all, I was very excited and impressed to see the worldwide collaboration on a pearl study using molecular biology technologies. While we are having fun playing with pearls and admiring their beauty, researchers are advancing the science and tech system using sophisticated tools and methodologies.

And thanks again for sharing the paper with us, @SteveM .

 

[CortezPearls]

Earlier this week, I received a set of beautiful T pearls that I found to match the peacock T pair I shared. They are not drilled yet. One or two of them if looked at closely are high button pearls. I am a bit hesitant whether I would like to drill them the conventional way, or from side to side.


Before sharing the pictures, I'd like to finally revisit the DNA fingerprinting paper. Honestly, I didn't understand the paper 100%, and my head is filled with tons of big and small question marks. I probably missed important information, too. Nonetheless, I'll ask a few here. Would appreciate if anyone bothers to answer, and all discussion is welcome.

1. I learned PCR-RFLP and understand how complicated it is. While I was reading the paper, I was wondering why they didn't directly do the sequencing of relevent genes (the "four target loci") on the PCR amplified adductor muscle specimens' DNAs and the pearl specimens' DNAs and just run a comparision of the sequences? Intuitively, same species' muscle DNA and pearl DNA would match, right? Why did they have to go through the whole complicated process of RFLP? Even 11 years ago, sequencing was not very expensive. I found online that in 2014, the cost of a human genome sequence dropped to $1,000. And that's a whole human genome's price we're talking about. A few specific oyster genes should be so much cheaper. Wikipedia also says "RFLP analysis is now largely obsolete due to the emergence of inexpensive DNA sequencing technologies". So, why did this group of researchers choose to use the complicated RFLP instead?

2. The method and logic in the paper seems to be based on the assumption that the DNA obtained from the pearl is the DNA of the oyster that carried the pearl, or at least the same species with that oyster. So I am curious, what is those organic matter between the bead and the nacre? I suspect that's the debris of the donor mantle tissue, is that correct? The epithelial cells in the donor tissue reproduce and develope into the pearl sac, but the tissue itself cannot 100% turn into the sac, and therefore some debris was trapped inside, am I understanding correctly?

3. To continue Question 2, I'm also curious: do ALL oysters EXCLUSIVELY use donor tissue from the same species for pearl production? I know that's what farmers do all the time, but is it a guarantee, like a 100% thing? Has anyone ever tried to put SoC pearl's tissue in Tahitian's shell, hoping to make large quantity SoC pearls? (Well, might need a new name if succeeded, LOL!) If that's too difficult because they are from different genera, how about P. Penguin's tissue into P. Sterna's oyster? Although SoC shell is smaller, it seems to produces decent size pearls more easily than Mabe Gai does. Did anyone ever try? If not, will it be possible? I understand even same species grafting already has a high death rate, and it would be intuitive to think cross-species and cross-genus will lead to even worse rate. But, if SoC could become more abundant and affordable, if Mabe Gai full pearls were more often seen on the market (instead of in a myth), how wonderful would that be...


Apologies for my crazy questions. According to a UK study, a lack of sleep lead to a lack of self-control. I was only able to sleep <4 hours last night and I feel like I'm sleepwalking all day today. So I forgive myself.

All in all, I was very excited and impressed to see the worldwide collaboration on a pearl study using molecular biology technologies. While we are having fun playing with pearls and admiring their beauty, researchers are advancing the science and tech system using sophisticated tools and methodologies.

And thanks again for sharing the paper with us, @SteveM .

To help answer your questions....and one is a bit out of my league since I am not a Geneticist:

1. I was wondering why they didn't directly do the sequencing of relevent genes (the "four target loci") on the PCR amplified adductor muscle specimens' DNAs and the pearl specimens' DNAs and just run a comparision of the sequences? Intuitively, same species' muscle DNA and pearl DNA would match, right? Right. They would match indeed...but the "Why" as to why they do it this way---beats me!

2. So I am curious, what is those organic matter between the bead and the nacre? I suspect that's the debris of the donor mantle tissue, is that correct? The epithelial cells in the donor tissue reproduce and developed into the pearl sac, but the tissue itself cannot 100% turn into the sac, and therefore some debris was trapped inside, am I understanding correctly? YES, you got this right. It is precisely as you state...and not only mantle tissue, there is also gonadic tissue -from the host- involved too.

3. do ALL oysters EXCLUSIVELY use donor tissue from the same species for pearl production? I know that's what farmers do all the time, but is it a guarantee, like a 100% thing? Has anyone ever tried to put SoC pearl's tissue in Tahitian's shell, hoping to make large quantity SoC pearls? Yes. We -pearl farmers- use the mantle from the same species. There have been many experiments about mantle tissue exchange and the results are from poor to full failures. I myself tried to use mantle from Pteria sterna in Pinctada mazatlanica and into other species such as the "Lion's Paw Scallop" (Nodipecten subnudosus) and it did not work. I mean...you have the specimens, the tools...and too many questions! You simply try! But you also see the results and then just stop trying.

 

[StarryPearl]

To help answer your questions....and one is a bit out of my league since I am not a Geneticist:

1. I was wondering why they didn't directly do the sequencing of relevent genes (the "four target loci") on the PCR amplified adductor muscle specimens' DNAs and the pearl specimens' DNAs and just run a comparision of the sequences? Intuitively, same species' muscle DNA and pearl DNA would match, right? Right. They would match indeed...but the "Why" as to why they do it this way---beats me!

2. So I am curious, what is those organic matter between the bead and the nacre? I suspect that's the debris of the donor mantle tissue, is that correct? The epithelial cells in the donor tissue reproduce and developed into the pearl sac, but the tissue itself cannot 100% turn into the sac, and therefore some debris was trapped inside, am I understanding correctly? YES, you got this right. It is precisely as you state...and not only mantle tissue, there is also gonadic tissue -from the host- involved too.

3. do ALL oysters EXCLUSIVELY use donor tissue from the same species for pearl production? I know that's what farmers do all the time, but is it a guarantee, like a 100% thing? Has anyone ever tried to put SoC pearl's tissue in Tahitian's shell, hoping to make large quantity SoC pearls? Yes. We -pearl farmers- use the mantle from the same species. There have been many experiments about mantle tissue exchange and the results are from poor to full failures. I myself tried to use mantle from Pteria sterna in Pinctada mazatlanica and into other species such as the "Lion's Paw Scallop" (Nodipecten subnudosus) and it did not work. I mean...you have the specimens, the tools...and too many questions! You simply try! But you also see the results and then just stop trying.

Thanks for answering my questions, Douglas.

So happy to hear that there have been experiments trying that!!I knew it! It must be so much fun!! I guess it might be just too difficult for the oysters to accept tissue from another genus. After all, oysters have a powerful immune system, too.

Do you recall seeing anyone trying grafting P. Penguin's tissue into P. Sterna's oyster? At least they are in the same genus. And at least in plants, it may work. "Genetically identical clones and intra-species plants have a high success rate for grafting. Grafting between species of the same genus is sometimes successful. Grafting has a low success rate when performed with plants in the same family but in different genera. — Wikipedia"

If we think it further, can we isolate the epithelial cells, proliferate them, and then implant with bead? Mammal epithelial cells isolation and culture seems quite mature. Has anyone figured out the technology with oyster? If that works out, not only the tissue-exchange grafting may have a better chance, but the best quality pearls' traits can be (hopefully) more easily replicated on larger number of pearls. Although we know epithelial cells do not proliferate forever like cancer cells do, we can still get the oyster "breeds" like cat breeds and dog breeds.

With that said, I love the current way of harvesting the best tissue and implanting it directly. Actually I might prefer this way to a lab way even if the lab isolating-proliferating-grafting approach is already there. Variety, mystery, and surprise are all elements that contribute to the beauty of pearls.