A slice off the old epidermis.

Human cloning work moves away from the embryo, but the reasons aren’t moral.

A recent Nature News article (abstract only) reports on the advances in stem cell cloning published in the last week. After using 15,000 monkey eggs in years of work to create embryonic stem cells, Mitalipov of Oregon Health & Science University successfully transplanted a skin cell nucleus into an egg, resulting in a line of cells with the ability to become many different kinds of tissue. The same week, two different groups reported making stem cells without eggs, by inserting a small suite of four genes. Each group, Yamanato’s from Kyoto University and Thompon’s from University of Wisconsin, used a different subset of genes.

Pleuripotent stem cells, those with the capacity to mature into many specific tissues, are the grail of research into cures for many diseases, including Parkinsons, ALS, and type I diabetes. Biologists have been able to make cells immortal in culture for decades, and even induce them to make a limited number of tissues, but the immortalization process always involved the use of genes also known to be involved in many cancers. This time, there are no known cancer linkages to the genes used.

The shift away from embryonic stem cells is one of pure practicality. Even the biologist behind Dolly, the first cloned sheep, created by the transfer of a nucleus into an egg, is abandoning the embryonic approach. The problem is low yield. The success rate for nuclear transfer into eggs is about 0.7%. However, President Bush and the cultural right have taken credit for the advance with as much pride as if they’d held the pipettes in the laboratory themselves.

About Peg.

Peg has a PhD in neuroscience and has a mind like a cocker spaniel. New scientific questions are like squeaky toys. She makes her living consulting with university faculty members on the fine art of grantsmanship, writes fiction for fun, and considers herself a wetware hacker.


  1. An astounding wetmachine-neutrino sighting!

    Welcome back, Peg!

    A dear friend of mine who is ardently “pro life” for the usual complex of reasons (most of which sound like casuistry to me, but let that go for the moment), was so thrilled by this news that she purchased 15 copies of USA Today to give to her friends when this story made it. It really is being accepted rather ecstatically and naively, imho, in some quarters.

    The slicing and dicing of random genes into a cell raises my proverbial eyebrow a few inches, but anything that increases the chance of therapeutic breakthroughs for the horrible diseases you mention is more than welcome to me, especially if it avoids heel-nipping and roadblocks from the “cultural right.”

    Anyway, I do hope we’ll see more from you now that you’ve broken the ice. We’ve missed you!

  2. Although the press is all about how this removes an active class of ethical objections to stem-cell research, the news is a genuine practical advance independent of moral issues. Specifically, by producing stem-cells from your own body, it is thought that the resulting tissue (brain cells, liver cells, bone marrow cells, etc.) will not be rejected when implanted into the donor.

    By the way, I owe my Croquet positions to a computer scientist (and PhD in Biology) who turned down the chance to head the Croquet development at the University of Wisconsin. He continued doing great Croquet work for a time while I was there, before being tapped by Jamie Thomson to go across the street to head bioinformatics at his lab. Ron Stewart is now one of the authors on the UW non-embryonic stem cell paper.

    They used a virus to reprogram skin cells to revert to a stem-cell. That’s a hell of a programming hack.

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