What do you think? Leave a respectful comment.

The video for this story is not available, but you can still read the transcript below.
No image

Scientists Reach Breakthrough in Cloning Monkey Embryos

Oregon scientists announced the successful cloning of monkey embryos this week, a major breakthrough in the field of stem cell research. NewsHour Health correspondent Susan Dentzer details their findings.

Read the Full Transcript

  • JIM LEHRER:

    Now, a development in stem cell research. Scientists say they have extracted embryonic stem cells from cloned monkey embryos. It's the first time that method has been successful with primates.

    Our health correspondent, Susan Dentzer, has more on this.

    Susan, welcome.

  • SUSAN DENTZER, NewsHour Health Correspondent:

    Thanks, Jim.

  • JIM LEHRER:

    First of all, who are the scientists, and where did they do their work?

  • SUSAN DENTZER:

    Jim, this is a team from Oregon Health and Science University. They're at the Oregon Primate Research Center, and they do research on primates, basically monkeys and apes.

  • JIM LEHRER:

    All right, now, what exactly have they done in this case?

  • SUSAN DENTZER:

    What they did was something that people have dreamed about doing for a long time, essentially taking an adult cell and turning back the clock, turning it into an embryonic cell that produces stem cells. And as we know, these are the cells that develop into any of the organs and tissues in the body.

    And so what they did was they took a skin cell from an adult, 9-year-old adult male rhesus monkey named Semos — he's named after a character in a "Planet of the Apes" movie. They took the skin cell. They took the nucleus of that cell, which has the nuclear DNA, the instructions for the cell. They stripped out that nucleus.

    Then, they took an egg cell from a very different female monkey, took the nucleus out of that, and you were left with the rest of the cell, which was the mitochondrial DNA. They took the nucleus from Semos. They stuck it into the rest of the egg cell.

    And, voila, you get a clone, in effect, of Semos, because what the cell — what you end up with is the cell with all of the nuclear content, the DNA nuclear content that Semos had. So, in effect, that creates an embryo.

    They then let that embryo grow for about five days to what's called the blastocyst stage. They then destroy the embryo and removed…

  • JIM LEHRER:

    Killed the embryos…

  • SUSAN DENTZER:

    … killed it — in effect, by pulling out the embryonic stem cells, you destroy the embryo. Then they took those stem cells. They were able to create two so-called lines of stem cells. And then they allowed those cells to differentiate into different kinds of cells, in one case, heart muscle cells and, in another case, neurons, nerve cells, showing that they could actually create these embryonic stem cells and differentiate them into higher orders of cells.

The Latest