Scientist
Profile:
Ian Wilmut
Keith Campbell
Wilmut and Campbell used the
udder cells of a Finn Doset sheep in their experiment.
From their 1995 cloning
experiment, Wilmut and Campbell
had learned that a newly fertilized egg entered a phase of
suspended animation as it coordinated its newly acquired DNA from sperm with its
own DNA. To simulate this state, they starved the adult
udder cells until they entered a suspended state, the G0 state, as they had
done in their earlier cloning experiments. Then, using an
electric current, they fused each cell with an enucleated unfertilized egg. By
starving the udder cells to get them to enter the same
suspended state, Wilmut and Campbell synchronized the cell cycles of the two cells.
This allowed the egg to take up the DNA of the
transplanted adult udder cell nucleus.
Of the 277 adult udder cells that they used to perform nuclear transfers, twenty-nine grew into developing embryos, which Wilmut and Campbell let incubate in sheep oviducts for a week before transferring each to surrogate mothers, which were Scottish blackface ewes.
Of these twenty-nine embryos,
one turned into a successful pregnancy, and on July 5,
1996, Dolly, the world's first mammal cloned from adult
cells, was born. The February 1997 announcement of
Dolly's birth absolutely shocked the scientific
community, who at the time generally believed that
cloning from adult cells could not be done. The discovery
also triggered a massive public debate about the ethics
of future cloning practices. PPL Theraputics, the principle
sponsor of Wilmut and Campbell's research, obtained the
patent rights on the cloning process.
Dolly photo courtesy of the Roslin Institute.
Overview of
the Nuclear Transfer technique.
The Roslin
Technique
The
Birth of Polly
Web Links:
The Roslin
Institute Online
Text of Wilmut's
Research Paper in Nature
Interview With Ian
Wilmut
[ Home ] [ The Details ] [ Reactions ] [ Interactions ] [ About Site ] [ Bibliography ]
Copyright 1998 by team 24355 and Kayotic Development.