Cloning confusion

In discussions about Aldous Huxley’s Brave New World, the topic of cloning inevitably surfaces. But, as we discussed briefly in class, the process of Bokanovskification doesn’t jibe with the definition of cloning or, in today’s more precise terminology, somatic cell nuclear transfer.

This modern-day cloning entails replacing the nucleus of an unfertilized egg with a donor nucleus from an adult cell, essentially making a copy of the donor. On the other hand, Huxley describes Bokanovsky’s Process as:

One egg, one embryo, one adult-normality. But a [fertilized] bokanovskified egg will bud, will proliferate, will divide. From eight to ninety-six buds, and every bud will grow into a perfectly formed embryo, and every embryo into a full-sized adult. Making ninety-six human beings grow where only one grew before. Progress. “Essentially,” the D.H.C. concluded, “bokanovskification consists of a series of arrests of development. We check the normal growth and, paradoxically enough, the egg responds by budding.”

In this process, the normal egg is fertilized by sperm just as it is in everyday, run-of-the-mill baby making. Only after the maternal and paternal genes unite do the scientists of Huxley’s world intervene by arresting the development of the fertilized egg (the zygote) to force it to “bud” and produce up to 96 identical siblings.

Accurately speaking, then, the members of a certain Bokanovsky group in Brave New World are not clones but simply identical twins, just as the director (and Huxley) describes them. In the development of identical twins, the zygote splits into two independent cells that then continue to develop into two humans. This phenomenon, via treatments with X-rays and chemicals, is reproduced many times in Bokanovsky’s process to induce multiple twinning, or “budding,” events.

An equivalent of Bokanovsky’s Process has already been carried out on human embryos. Nearly fifteen years ago, in October of 1993, Dr. Stillman and Dr. Hall of George Washington University artificially twinned a human zygote to produce up to eight human embryos, much like in the scenario Huxley laid out. Instead of using radiation and chemicals, however, they simply manually separated the two cells resulting from the division of the zygote, creating “artificial twins.”

Much the same confusion about cloning versus twinning arose as a result of the work of Stillman and Hall, as was seen in a New York Times article covering the story. In the headline itself, the reporter incorrectly refers to this process of artificial twinning as cloning. Later in the story, the journalist makes another error when she states, “Cloning, the creation of organisms with an identical set of genes, occurs naturally in humans in the case of identical twins.”

This definition of cloning should read something more like “the creation of an organism with an identical set of genes to an adult donor,” a process conspicuously absent from Brave New World.

 

Chris Adkins

As a side note, I’d like to reiterate what I said in class: Bokanovsky’s Process doesn’t resemble parthenogenesis any more than it does cloning. In artificial parthenogenesis (the process described in the President’s Bioethics Committee’s report), an unfertilized egg replicates its own DNA and then goes on to produce a female offspring that is exactly genetically identical (mitochondrial DNA and all) to the mother.

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~ by slipstream99 on February 4, 2008.

2 Responses to “Cloning confusion”

  1. Thank you for this helpful set of definitions and for the reference to the NYT article. I want to suggest a revision to your penultimate paragraph: rather than say “adult donor,” shouldn’t you say simply “doner”? After all, one could clone an infant.

  2. Yes, I was just trying to make the point that the donor nucleus must come from a differentiated – essentially, an “adult” or “mature” cell – to be truly considered somatic cell nuclear transfer.

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