This article was created to discuss recent biomedical and biotechnological advancements. To make this material accessible to all, it is written in a conversational format between my biologist friend Dr. Watson and me. I hope that this will be educational for those who are interested in science, but also want to be entertained.
Dave: Dr. Watson, here is my question. I know that there have been some major technological breakthroughs in biotechnology in the past three years, including the completion of the Human Genome Project, International HapMap project, human stem cells research, cloning of various mammalian species, and development of non-Sanger DNA sequencing. Now, do you think it is possible to clone Anastasia or a family member of Tsar Nicholas II?
Dr. W: Dave, first of all, I must stress that almost all scientists are strongly against “reproductive cloning” for ethical reasons. Seriously, I do not know any real scientist who is for it, at least in the United States. Reproductive cloning is completely different from “therapeutic cloning”.
Dave: I know. I believe that that’s why reproductive cloning is legally banned anyway.
Dr. W: Actually, you are wrong about that. United States Congress never passed a law that banned cloning. This is because there is a conflict between Comprehensive Human Cloning ban and Partial ban. So it is legally possible, at least at this moment, although no serious scientist would want to do it.
Dave: Is it? After five years of the Bush administration? Wow. Anyway, the point here is to ask about the technical aspect. Is the technology there? Or a potential technique?
Dr. W: OK. I know you are writing this article possibly for someone like a high school student who is interested in science, and should be able to understand this. I will keep that in mind and try my best to explain. Actually, the question is a GREAT question for many reasons. Just five years ago, anyone would dismiss such a question as pure fantasy. It was a laugh-out-loud question. But amazingly now, at least in principle, the answer is YES. Of course, there would be a whole bunch of technological obstacles, but it’s not a fantasy anymore.
Dave: But what’s the big deal? If there is no financial limit, we can even clone a dinosaur, at least “in principle”, right?
Dr. W: No. You are talking about Jurassic Park stuff here. If you want to talk about science seriously, you have to distinguish fiction and reality. That movie is 100% based purely on fantasy. It’s not even possible “in principle”.
Dave: Why is that? Those mosquitoes in amber may contain dinosaur blood. And you could get DNA from the blood.
Dr. W: Yes, there is a mosquito in amber. But no one was ever able to collect any dinosaur DNA from it. Never. Even if you get DNA, there is no way to clone a dinosaur with current technology. There is no way to microinject the chromosome and implant it.
Dave: That’s what I thought you would say. But I thought that Scott R. Woodward of Brigham Young University reported that he obtained dinosaur DNA in 1995.
Dr. W: Yes. There was a paper. But as far as I know, almost everyone now thinks that DNA was contamination from human DNA. The result was an artifact. That’s why amateurs have to be careful with this. Because the general public only believes what they see with their eyes. A mosquito in amber LOOKS very well preserved to our eye. But biochemically speaking, they are garbage! All the DNA is completely degraded. You have to think chemically, which requires a certain amount of training. Yes. DNA is a very stable molecule. But it has limits. As a matter of fact, DNA doesn’t survive over 100,000 years. Except for rare conditions where samples are extremely well preserved - there was a case where it survived for 400,000 years. But the dinosaur was extinct some 65,000,000 years ago!
Dave: I see, I understand. But the Romanov family’s DNA is just some 80 years old. That would make recovery of DNA easier, wouldn’t it?
Dr. W: Not if you are interested in nuclear DNA. Remember, there are two types of DNA. Mitochondrial (mtDNA) and nuclear DNA. When I said DNA could survive for 100,000 years, I was talking about mtDNA. Nuclear DNA is much more difficult to preserve. Generally, it would be difficult to recover it by PCR after a few decades.
Dave: Oh, then we CANNOT clone Anastasia and her family members? But if you want to clone a human baby, there is no technological problem, right? I just saw a newspaper that someone in Florida cloned a baby. Is this true?
Dr. W: Which newspaper? National Enquirer? Sun? Unfortunately, sometimes even mainstream newspapers run hoax news like this. No, there is no evidence that shows that a human baby was ever cloned. Not a single baby!
Raelian religious sect spokeswoman told the press that they cloned a baby.
Dave: Oh, why is that? Is a human more difficult to clone than other animals?
Dr.W: No, mainly because of ethical reasons no one ever cloned a human. But considering that we cloned other mammals: sheep, mice, cows, pigs, horses, cats, dogs, rabbits, and deer in the past decade, there is no reason to believe that human cloning is technically more difficult than other animals. Although there is a chance that first human cloned baby may have some genetic disease.
Dave: That’s unethical. We cannot use a human baby as a guinea pig.
Dr. W: This is the main reason why reproductive cloning is unethical. But what if you establish the technology to produce a baby who is as healthy as one from normal reproduction? Some people may not think it’s as unethical as others. For example, if the parents have a genetic disease and there is a risk to produce genetically abnormal baby, but successfully had a first baby who was very healthy. Is it unethical to clone the second baby from your first baby? What you are doing is just making “delayed identical twins”.
Dave: I would say it’s unethical, but the decision should be up to the parents, not up to me, or the government. Just like abortion is unethical, but the decision is up to the parents.
Dr. W: Some people think the government should interfere. But we won’t discuss it here.
Dave: So all we have to do is get DNA from the bones of the imperial family and clone them.
Dr. W: Not so simple. Cloning someone who is living and cloning someone who is dead are two completely different things. Actually, including animals, no scientist ever cloned any living thing from a dead sample.
Dave: Oh, so then how do we do it?
Dr. W: Science is thinking about something that has never been done before. That’s why I said that this is a great question. Let’s call our pretend experiment “The Anastasia Cloning Project” and divide our tasks into 4 parts:
1. Obtain DNA molecules from bones.
2. Get a DNA sequence.
3. Reconstruct the total DNA sequence (genome).
4. Construct the chromosomes.
5. Inject chromosomes into somatic cells that have the mitochondria of the Tsarina.
6. Find a surrogate mother for Anastasia.
7. Raise Anastasia in an environment that is similar to the natural gestational conditions
Technical problems of cloning from ancient DNA in 1996:
Dave: I am not sure there would be someone from the Tsarina’s descendants who would cooperate with this project to provide the mtDNA. But I am sure that there would be lots of women who would like to give birth to Anastasia though. Task #7 might not be so easy. It would be best to raise Anastasia at the Alexander Palace in Tsarskoe Selo, but I am not sure if the people of Pushkin would cooperate with this.
Dr. W: But all these are non-science issues. The point is that all the tasks, at least in principle, can be resolved by current technology. I won’t discuss the technological details here, but I encourage everyone to think and explore the literature if you are interested in this. You can start by reading an article called “Genomic Sequencing of Pleistocene Cave Bears.” (Science. 2005 Jul 22;309(5734):597-9).
Dave: Thank you very much!
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Read about the Chimpanzee Genome Project
and the Neanderthal Genome Project.
